A single lvl 5 sorcerer can defeat one, using no weird gimmicks or feat / multiclass. If it dashes and uses legendary action, it can move a maximum of 75 feet per round. If the sorcerer casts extended haste on itself and uses its haste action to just run away, it can easily out pace the demilich.
Not only that, but none of the lich’s abilities have a range further then 30 feet, so even if he did almost catch up, nothing would happen.
From there the player can just cast strength / dex / con save spells against it, since it only has a -5 / +5 / +6 to those, respectively.
Some great options would be Arms of Hadar and Maxiliman’s earthen grasp, but regular old fireball also gets the job done, since it only has 80 HP and no resistance to elemental damage.
It is very unlikely you will encounter a demilich in a wide open space that would allow for such running around. They are the remnants of liches, and would likely be found in tombs, ruins, or lairs, all of which would generally be on the smaller side. It also just looks like a skull, so it is highly possible to get close to it before realizing it...in fact it doesn't even activate until it is disturbed, at least per the MM entry
It has the avoidance trait, which means any of those save spells you mention that have save for half damage rules, it's either taking half damage or no damage. it also has 3 uses of legendary resistance to spend.
The specific spells you mention are worse than useless against the thing
Arms of Hadar erupt from you, which means you have to be no more than 10 feet away from the lich to damage it. Also, see avoidance trait
Maxilmilian's earthen grasp erupts from the ground and is medium size...the demilich flies, so ten feet in the air negates it entirely. However if for some reason the demilich is close enough to be grabbed this would be a decent spell to use.
Fireball...see avoidance
Now, if you do happen to get close to it, possibly because it just looks like a skull or is hidden, or it used it's DC 19 Dex save or fall prone lair action first thing, its howl is either going to drop you outright, or up to three of you are going to be hit with its life drain attack. Then it will exhaust its legendary actions to blind, further harm, or curse you.
Also, your non-spellcasters are going to have trouble with it, since it has 20 AC, resists damage from magical weapons and is immune to non-magical weapons, and it does carry a number of condition and damage immunities that ward off other spells. It also has ridiculous save bonuses against 3 types of save, decent save bonuses against 2, and the one it has a crappy save against is a fairly rare type of spell save.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
On the 50:50 chance that itnsctually gets to use a lair action that turn, and targets the Paladin with with antimagic field and not another character or uses a different lair action? And since antimagic field doesn't affect effects provided by deities, which Divine Smite is, then Divine Smite works fine.
I'm not jumping in with too much with the CR things since I don't have much experience, but I think you're giving too much weight to the lair actions making it fine. And if it's in its lair it's CR20, not CR18, so, honestly now, do you think that it would provide a deadly encounter to 4 L19 characters? 4 L19 Paladins? Because that's what a CR20 creature does, to my understanding.
If you're not willing or able to to discuss in good faith, then don't be surprised if I don't respond, there are better things in life for me to do than humour you. This signature is that response.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
On the 50:50 chance that itnsctually gets to use a lair action that turn, and targets the Paladin with with antimagic field and not another character or uses a different lair action? And since antimagic field doesn't affect effects provided by deities, which Divine Smite is, then Divine Smite works fine.
I'm not jumping in with too much with the CR things since I don't have much experience, but I think you're giving too much weight to the lair actions making it fine. And if it's in its lair it's CR20, not CR18, so, honestly now, do you think that it would provide a deadly encounter to 4 L19 characters? 4 L19 Paladins? Because that's what a CR20 creature does, to my understanding.
The designers didn't playtest it. A party of 4 level 15's will cut through 80 hit points in a round. It gets really bad if there is a paladin in the party. They are relying heavy on gimmicks to keep 80 hit points up, but any DM worth their salt will know he's going to be dead quickly. You'd have to run your parties resources below 80% and have them be at half health and he'd be a moderate encounter for a group of 4 level 18's maybe, closer to easy. Now if you have a completely unoptimized party of goofballs who spends 3 turns talking with the demi-lich to give him time to get his debuffs up, sure its CR18, but to that party a Goblin would be a CR 5.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
I mean, even with that mistake, that’s still only 3d8 damage, assuming every attack hits.
It's effective hp is about 300 it just so happens that paladins have damage specifically designed to take down undead and that doesnt trigger it's resistances and immunities. Also if the dm wanted to really be a dick technically the demi lich can just use its legendary actions to completely move out of range of the paladin when they come close as a legendary action ignoring initiative. A paladin is not smiting this thing on the first round or potentially ever unless the dm ****s up or the party finds a way to help the paladin do it.
Cr is really not designed around the idea of counter play but instead generally about the health, damage and resistances. The way the demilich works is its hard to kill because it's so hard to hit, has so many resistances/immunites, is able to heal itself and flies. It's offense is its main weakness but the longer its around the more likely that howl is to hit which it can move 75ft and still use. I'd be careful about bumping it's health because of those defences each hp point goes further than it would normally for example 200 hp as you suggest puts it's defenses on par with cr 28 monsters and gives it about 700 effective hp based on online calculators.
What I will say is the Cr seems to be calculated to basically ignore its offensive abilities likely because it does have that chance of an instant kill and it in my opinion does not have the offences to justify CR 18. it's defense is appropriate for cr 18 but doesn't exceed it like you might expect for such and offensively mediocre monster.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
I mean, even with that mistake, that’s still only 3d8 damage, assuming every attack hits.
At level 11, paladins get improved divine smite so they add an extra 1d8 radiant. Smites on undead add an extra 1d8. Smite base damage is 2d8 + 1d8 per spell slot over 1. A level 15 paladin gets two level 4 spell slots so:
1d8 improved
+
1d8 undead
+
2d8 base smite
+
+3d8 level 4 slot
= 7d8 base smite or 58 hit points, they get two of them so 116 max at level 4, then add in that level 3 smite at 48, max being 168 smite damage excluding weapon, cut that in half for average its 82 damage radiant excluding weapon damage, from a single PC vs a CR 18 that has 80 hps. The game designers didn't play test the demilich.
Finding a party without a paladin for campaign play is just about impossible. The charisma bonus to saves makes the Paladin a required class. I've run 3 long term 5E campaigns and at session zero they always make sure there is a paladin for saves.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
big assumption that any PC would have two magic weapons, for one, but lets play this out. Lets say the Paladin wins initiative with a 20 or higher (so it avoids the lair actions) and is close enough to approach the demi-lich in melee range without having to dash (which is a fairly tall order when all combined).
Vengeance Paladin, level 15 would have two attacks with advantage (using it's bonus action to gain the advantage with Vow of Enmity) and +10 to hit. Assuming that both attacks hit against AC 20 (which is admittedly likely as both rolls would have to be 9 or lower), that is 2(weapon damage + 7d8 + mod). assuming d8 weapons, that is 16d8 +10. The demilich will resist 2d8+10 of the damage (reducing the damage to avg 9) and take 14d8 direct for a total of 56 +9 or 65 damage...so not dead.
Taking the advantage away to add the offhand attack severely reduces the chance of a hit (statistically, at least one of the attacks will miss since each attack is a 50/50 chance) but adds the additional 3rd level smite. So if all three attacks hit (statistically unlikely), you could then one shot the demi-lich. But again, that first assumes every attack hits, and you meet the preliminary criteria.
Ultimately, one class whose whole point is nova damage shouldn't be dictating the CR of creatures though. There is no guarantee that a party would have that class present.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
I mean, even with that mistake, that’s still only 3d8 damage, assuming every attack hits.
At level 11, paladins get improved divine smite so they add an extra 1d8 radiant. Smites on undead add an extra 1d8. Smite base damage is 2d8 + 1d8 per spell slot over 1. A level 15 paladin gets two level 4 spell slots so:
1d8 improved
+
1d8 undead
+
2d8 base smite
+
+3d8 level 4 slot
= 7d8 base smite or 58 hit points, they get two of them so 116 max at level 4, then add in that level 3 smite at 48, max being 168 smite damage excluding weapon, cut that in half for average its 82 damage radiant excluding weapon damage, from a single PC vs a CR 18 that has 80 hps. The game designers didn't play test the demilich.
Why the heck are you assuming max damage though? 7d8 is average 31 damage. only about 1 time in 50 would you roll maximum damage.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
big assumption that any PC would have two magic weapons, for one, but lets play this out. Lets say the Paladin wins initiative with a 20 or higher (so it avoids the lair actions) and is close enough to approach the demi-lich in melee range without having to dash (which is a fairly tall order when all combined).
Vengeance Paladin, level 15 would have two attacks with advantage (using it's bonus action to gain the advantage with Vow of Enmity) and +10 to hit. Assuming that both attacks hit against AC 20 (which is admittedly likely as both rolls would have to be 9 or lower), that is 2(weapon damage + 7d8 + mod). assuming d8 weapons, that is 16d8 +10. The demilich will resist 2d8+10 of the damage (reducing the damage to avg 9) and take 14d8 direct for a total of 56 +9 or 65 damage...so not dead.
Taking the advantage away to add the offhand attack severely reduces the chance of a hit (statistically, at least one of the attacks will miss since each attack is a 50/50 chance) but adds the additional 3rd level smite. So if all three attacks hit (statistically unlikely), you could then one shot the demi-lich. But again, that first assumes every attack hits, and you meet the preliminary criteria.
Ultimately, one class whose whole point is nova damage shouldn't be dictating the CR of creatures though. There is no guarantee that a party would have that class present.
A rogue would nova the Demilich as well, they are DPS classes, they exist in the game for a reason. You can't put a CR 18 on a mob with that little hit points. From the DMG the Demilich has the Hit Points of a CR1 monster, you know that right? A CR 18 is between 326 and 340 hit points.
Do you feel threatened that your game designers capabilities are questioned when they don't even follow their own guidelines? Even factoring in magic and abilities its got 75% less hit points than it should for a CR 18. You've run high level campaigns right, you know player DPS capabilities right? Maybe a party of 4 level 12's as a boss encounter it might work, but 4 level 18's its a guaranteed kill most likely less than a round if that.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
big assumption that any PC would have two magic weapons, for one, but lets play this out. Lets say the Paladin wins initiative with a 20 or higher (so it avoids the lair actions) and is close enough to approach the demi-lich in melee range without having to dash (which is a fairly tall order when all combined).
Vengeance Paladin, level 15 would have two attacks with advantage (using it's bonus action to gain the advantage with Vow of Enmity) and +10 to hit. Assuming that both attacks hit against AC 20 (which is admittedly likely as both rolls would have to be 9 or lower), that is 2(weapon damage + 7d8 + mod). assuming d8 weapons, that is 16d8 +10. The demilich will resist 2d8+10 of the damage (reducing the damage to avg 9) and take 14d8 direct for a total of 56 +9 or 65 damage...so not dead.
Taking the advantage away to add the offhand attack severely reduces the chance of a hit (statistically, at least one of the attacks will miss since each attack is a 50/50 chance) but adds the additional 3rd level smite. So if all three attacks hit (statistically unlikely), you could then one shot the demi-lich. But again, that first assumes every attack hits, and you meet the preliminary criteria.
Ultimately, one class whose whole point is nova damage shouldn't be dictating the CR of creatures though. There is no guarantee that a party would have that class present.
A rogue would nova the Demilich as well, they are DPS classes, they exist in the game for a reason. You can't put a CR 18 on a mob with that little hit points. From the DMG the Demilich has the Hit Points of a CR1 monster, you know that right? A CR 18 is between 326 and 340 hit points.
Do you feel threatened that your game designers capabilities are questioned when they don't even follow their own guidelines? Even factoring in magic and abilities its got 75% less hit points than it should for a CR 18. You've run high level campaigns right, you know player DPS capabilities right? Maybe a party of 4 level 12's as a boss encounter it might work, but 4 level 18's its a guaranteed kill most likely less than a round if that.
A Demi-lich is practically a medium encounter for a group of 4 level 18s and a deadly encounter for level 12s...so that seems accurate to me.
And I'm not sure why you are getting so heated...I absolutely am not threatened by the fact that an official creature doesn't conform to the DMG rules. It's not the only one by a long shot. It seems like a decent Tier 3 boss/miniboss monster, nothing more.
At level 11, paladins get improved divine smite so they add an extra 1d8 radiant. Smites on undead add an extra 1d8. Smite base damage is 2d8 + 1d8 per spell slot over 1. A level 15 paladin gets two level 4 spell slots so:
1d8 improved
+
1d8 undead
+
2d8 base smite
+
+3d8 level 4 slot
= 7d8 base smite or 58 hit points, they get two of them so 116 max at level 4, then add in that level 3 smite at 48, max being 168 smite damage excluding weapon, cut that in half for average its 82 damage radiant excluding weapon damage, from a single PC vs a CR 18 that has 80 hps. The game designers didn't play test the demilich.
Finding a party without a paladin for campaign play is just about impossible. The charisma bonus to saves makes the Paladin a required class. I've run 3 long term 5E campaigns and at session zero they always make sure there is a paladin for saves.
Only the 1d8 from Improved Smite is non-magical; everything else doesn't work in an anti-magic field. I'm not going to address your unhinged "required paladin" tripe.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
And what tomb would be designed in such a way that would allow this to happen?
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
I mean, even with that mistake, that’s still only 3d8 damage, assuming every attack hits.
At level 11, paladins get improved divine smite so they add an extra 1d8 radiant. Smites on undead add an extra 1d8. Smite base damage is 2d8 + 1d8 per spell slot over 1. A level 15 paladin gets two level 4 spell slots so:
1d8 improved
+
1d8 undead
+
2d8 base smite
+
+3d8 level 4 slot
= 7d8 base smite or 58 hit points, they get two of them so 116 max at level 4, then add in that level 3 smite at 48, max being 168 smite damage excluding weapon, cut that in half for average its 82 damage radiant excluding weapon damage, from a single PC vs a CR 18 that has 80 hps. The game designers didn't play test the demilich.
Why the heck are you assuming max damage though? 7d8 is average 31 damage. only about 1 time in 50 would you roll maximum damage.
Max Damage of 7 X 8 = 56. A level 15 Paladin makes two attacks with his main hand meaning what 2 X 56 = 112 damage, now cut that in half for average meaning with his main hand on average with smite damage alone he hits for 56. By time you take a level 15 paladin having a +10 to hit + Advantage adding in a + 4.25 to hit meaning +14.25 vs AC 20, meaning he's going to hit approximately 70% of the time, its highly likely both hits will strike and averaging out the damage it will take 56 hits points of damage. Now, oath of vengeance is a bonus action to add in, so if they don't go for it and just go with the standard +10 to hit so they can use the bonus action to get in the offhand to hand as well, still a good chance at one shotting by himself. Even if he doesn't the rest of the party will most likely remove the demilich on rd 1.
Again I'm assuming you've DM'd high level play you know the damage a party can put out and understand that 80 hit points is about 2 players DPS at level 18 easily.
Assuming you got sneak attack a rogue would be more likely to kill it first round than a paladin but i think sneak attack would be really hard to get. It has true sight, flies and immunity to several conditions that would give advantage. If you have the optional rule where the rogue can get sneak attack by not moving then yes the demilich is in trouble, otherwise I don't think a rogue is actually going to get sneak attack.
The strength of the demilichs defense is that it blocks allot of abilities, it can avoid the melee attacks of paladin easily, sneak attacks and most spells.
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Just noticed something weird about demiliches :
A single lvl 5 sorcerer can defeat one, using no weird gimmicks or feat / multiclass. If it dashes and uses legendary action, it can move a maximum of 75 feet per round.
If the sorcerer casts extended haste on itself and uses its haste action to just run away, it can easily out pace the demilich.
Not only that, but none of the lich’s abilities have a range further then 30 feet, so even if he did almost catch up, nothing would happen.
From there the player can just cast strength / dex / con save spells against it, since it only has a -5 / +5 / +6 to those, respectively.
Some great options would be Arms of Hadar and Maxiliman’s earthen grasp, but regular old fireball also gets the job done, since it only has 80 HP and no resistance to elemental damage.
Have fun grinding them!
And what tomb would be designed in such a way that would allow this to happen?
My homebrew content: Monsters, subclasses, Magic items, Feats, spells, races, backgrounds
A few things to consider:
A dual wielding Level 15 Paladin solo that wins initiative one shots the demi-lich doing 92 hit points damage with at least a 50% chance to hit.
Its the standard problem of of CR balancing at higher levels. Its almost like the game designers didn't play a lot of the monsters in a fight with a an average party before publishing. Its a CR 10 monster as designed, not CR 18. If they move the Demi-liches hitpoints into the mid 200's its a CR18. The monster doesn't have the hit points to stay alive long enough to use its abilities.
Is that 92 damage after resistances? because if your paladin is doing the 184 damage with a magic weapon required to achieve that damage total, that pretty impressive. If either dual wielded weapon is non-magical, then that damage is negated because the demilich is immune.
Also, your stance assumes the paladin 1) wins initiative, 2) started combat close enough to the demilich to reach it without dashing, and 3) hits all its attacks (against AC 20). It also assumes that the paladin had a initiative >20 as otherwise it will have to deal with one of a number of nasty lair actions first, including the personal antimagic field which would effectively reduce that paladin's first turn damage to a big ol' zero. (since its weapons would be non-magical and it's spells wouldn't work)
A level 15 paladin will have two magic weapons and should have at least a +10 to hit at 15, if they are playing vengeance, as a bonus action they now have advantage on hits meaning they have a +14.25 to hit. The majority of the damage is coming from smites. He can do two level 4 smites 5d8 + 1d8 (undead) + 1d8 (class feature) so 7d8 X 2 and a 6d8 for a level 3 smite = 80 hp smit damage alone ignoring weapon damage.
The Demilich doesn't have the hit points to be a CR 18 let alone the hit points to use its lair actions, it needs to be in the mid 200's to be a CR 18.
Excepts they won't do that, because a paladin will never have enough initiative to beat lair actions.
So the lich triggers antimagic, they lose their magical weapons and smiting, including the base damage provided by improved divine smite. Then you get nothing, because their weapons are non-magical, and your ****ed.
My homebrew content: Monsters, subclasses, Magic items, Feats, spells, races, backgrounds
The improved divine smite does not get negated by anti-magic field. You obviously are very invested in the DemiLich being a CR 18, so congratulations to make you feel better I'll write its a CR 18. Everyone who read the basic stats I wrote, ignore it. The Demilich is a true CR 18, we all know it, it has been said.
On the 50:50 chance that itnsctually gets to use a lair action that turn, and targets the Paladin with with antimagic field and not another character or uses a different lair action? And since antimagic field doesn't affect effects provided by deities, which Divine Smite is, then Divine Smite works fine.
I'm not jumping in with too much with the CR things since I don't have much experience, but I think you're giving too much weight to the lair actions making it fine. And if it's in its lair it's CR20, not CR18, so, honestly now, do you think that it would provide a deadly encounter to 4 L19 characters? 4 L19 Paladins? Because that's what a CR20 creature does, to my understanding.
If you're not willing or able to to discuss in good faith, then don't be surprised if I don't respond, there are better things in life for me to do than humour you. This signature is that response.
The designers didn't playtest it. A party of 4 level 15's will cut through 80 hit points in a round. It gets really bad if there is a paladin in the party. They are relying heavy on gimmicks to keep 80 hit points up, but any DM worth their salt will know he's going to be dead quickly. You'd have to run your parties resources below 80% and have them be at half health and he'd be a moderate encounter for a group of 4 level 18's maybe, closer to easy. Now if you have a completely unoptimized party of goofballs who spends 3 turns talking with the demi-lich to give him time to get his debuffs up, sure its CR18, but to that party a Goblin would be a CR 5.
I mean, even with that mistake, that’s still only 3d8 damage, assuming every attack hits.
It's effective hp is about 300 it just so happens that paladins have damage specifically designed to take down undead and that doesnt trigger it's resistances and immunities. Also if the dm wanted to really be a dick technically the demi lich can just use its legendary actions to completely move out of range of the paladin when they come close as a legendary action ignoring initiative. A paladin is not smiting this thing on the first round or potentially ever unless the dm ****s up or the party finds a way to help the paladin do it.
Cr is really not designed around the idea of counter play but instead generally about the health, damage and resistances. The way the demilich works is its hard to kill because it's so hard to hit, has so many resistances/immunites, is able to heal itself and flies. It's offense is its main weakness but the longer its around the more likely that howl is to hit which it can move 75ft and still use. I'd be careful about bumping it's health because of those defences each hp point goes further than it would normally for example 200 hp as you suggest puts it's defenses on par with cr 28 monsters and gives it about 700 effective hp based on online calculators.
What I will say is the Cr seems to be calculated to basically ignore its offensive abilities likely because it does have that chance of an instant kill and it in my opinion does not have the offences to justify CR 18. it's defense is appropriate for cr 18 but doesn't exceed it like you might expect for such and offensively mediocre monster.
At level 11, paladins get improved divine smite so they add an extra 1d8 radiant. Smites on undead add an extra 1d8. Smite base damage is 2d8 + 1d8 per spell slot over 1. A level 15 paladin gets two level 4 spell slots so:
1d8 improved
+
1d8 undead
+
2d8 base smite
+
+3d8 level 4 slot
= 7d8 base smite or 58 hit points, they get two of them so 116 max at level 4, then add in that level 3 smite at 48, max being 168 smite damage excluding weapon, cut that in half for average its 82 damage radiant excluding weapon damage, from a single PC vs a CR 18 that has 80 hps. The game designers didn't play test the demilich.
Finding a party without a paladin for campaign play is just about impossible. The charisma bonus to saves makes the Paladin a required class. I've run 3 long term 5E campaigns and at session zero they always make sure there is a paladin for saves.
big assumption that any PC would have two magic weapons, for one, but lets play this out. Lets say the Paladin wins initiative with a 20 or higher (so it avoids the lair actions) and is close enough to approach the demi-lich in melee range without having to dash (which is a fairly tall order when all combined).
Vengeance Paladin, level 15 would have two attacks with advantage (using it's bonus action to gain the advantage with Vow of Enmity) and +10 to hit. Assuming that both attacks hit against AC 20 (which is admittedly likely as both rolls would have to be 9 or lower), that is 2(weapon damage + 7d8 + mod). assuming d8 weapons, that is 16d8 +10. The demilich will resist 2d8+10 of the damage (reducing the damage to avg 9) and take 14d8 direct for a total of 56 +9 or 65 damage...so not dead.
Taking the advantage away to add the offhand attack severely reduces the chance of a hit (statistically, at least one of the attacks will miss since each attack is a 50/50 chance) but adds the additional 3rd level smite. So if all three attacks hit (statistically unlikely), you could then one shot the demi-lich. But again, that first assumes every attack hits, and you meet the preliminary criteria.
Ultimately, one class whose whole point is nova damage shouldn't be dictating the CR of creatures though. There is no guarantee that a party would have that class present.
It doesn'
Why the heck are you assuming max damage though? 7d8 is average 31 damage. only about 1 time in 50 would you roll maximum damage.
A rogue would nova the Demilich as well, they are DPS classes, they exist in the game for a reason. You can't put a CR 18 on a mob with that little hit points. From the DMG the Demilich has the Hit Points of a CR1 monster, you know that right? A CR 18 is between 326 and 340 hit points.
Do you feel threatened that your game designers capabilities are questioned when they don't even follow their own guidelines? Even factoring in magic and abilities its got 75% less hit points than it should for a CR 18. You've run high level campaigns right, you know player DPS capabilities right? Maybe a party of 4 level 12's as a boss encounter it might work, but 4 level 18's its a guaranteed kill most likely less than a round if that.
A Demi-lich is practically a medium encounter for a group of 4 level 18s and a deadly encounter for level 12s...so that seems accurate to me.
And I'm not sure why you are getting so heated...I absolutely am not threatened by the fact that an official creature doesn't conform to the DMG rules. It's not the only one by a long shot. It seems like a decent Tier 3 boss/miniboss monster, nothing more.
Only the 1d8 from Improved Smite is non-magical; everything else doesn't work in an anti-magic field. I'm not going to address your unhinged "required paladin" tripe.
Max Damage of 7 X 8 = 56. A level 15 Paladin makes two attacks with his main hand meaning what 2 X 56 = 112 damage, now cut that in half for average meaning with his main hand on average with smite damage alone he hits for 56. By time you take a level 15 paladin having a +10 to hit + Advantage adding in a + 4.25 to hit meaning +14.25 vs AC 20, meaning he's going to hit approximately 70% of the time, its highly likely both hits will strike and averaging out the damage it will take 56 hits points of damage. Now, oath of vengeance is a bonus action to add in, so if they don't go for it and just go with the standard +10 to hit so they can use the bonus action to get in the offhand to hand as well, still a good chance at one shotting by himself. Even if he doesn't the rest of the party will most likely remove the demilich on rd 1.
Again I'm assuming you've DM'd high level play you know the damage a party can put out and understand that 80 hit points is about 2 players DPS at level 18 easily.
Assuming you got sneak attack a rogue would be more likely to kill it first round than a paladin but i think sneak attack would be really hard to get. It has true sight, flies and immunity to several conditions that would give advantage. If you have the optional rule where the rogue can get sneak attack by not moving then yes the demilich is in trouble, otherwise I don't think a rogue is actually going to get sneak attack.
The strength of the demilichs defense is that it blocks allot of abilities, it can avoid the melee attacks of paladin easily, sneak attacks and most spells.