Demiliches should not be CR 18

So, playing around with the DMG:

• HP is 80. Since expected CR is 18, HP multiplier for resistances and immunities is x1.25. Legendary Resistance is giving it another 90, total effective hp 190.
• Avoidance increases effective AC by 1.
• Life Drain should probably increase defensive CR, but there is no formula for how to do so. We'll ignore it for now.
• Basic defensive CR is 8 (from effective hit points) +2 (effective AC 21 is 5 over the expected 16)
• Offensive CR depends on how you value Howl. If you ignore it, figure Life Drain hits 2 targets/turn (its range is quite short, so probably won't hit 3) for 42 dpr. Energy Drain doesn't actually do any damage unless it reduces max hp below current hp, so figure it's worth 3 dpr. 45 dpr is an offensive CR of 7, increased to 9 due to save DC.

Overall, yeah, looks like a CR in the 10 range -- maybe a bit more because you have to recalculate effective hp for the lower CR and for the factors we haven't valued, but probably not over 12.

Yeah I looked it up it, it looks like a mistake. It was originally 20d4 take the maximum instead of average but they changed it to 32d4 in an errata without changing the undead trait. So it's unclear if they changed it to 32d4 intending it to use the average instead of max  and just forgot to change undead nature or it was intended to have it's hp go up to 124. Its most likely the former. 

https://media.wizards.com/2018/dnd/downloads/MM-Errata.pdf

There's not enough talk of Howl in this discussion. If we're talking about the ideal scenario for a PC paladin, let's talk about the same thing for the demilich - it could literally fly from around a corner, Howl in the middle of a high level party, and TPK it before anyone gets a turn. Game over, just like that.

Yes, a high-level party will likely have ways to mitigate that scenario and 15 is not a particularly challenging DC (but it is still fail-able by everyone). But how do you measure the threat level of something like that? 5e has mostly done away with such extreme save-or-suck effects, and when it tries to incorporate them it's not surprising that their math would break down.

I mean CR is a garbage metric anyway - especially at high levels - but this monster isn't rated particularly worse than others in my mind. It's just a glass cannon. My only experience with it in play was in a fight with several other creatures, and it was an effective and terrifying part of the encounter.

Quote from scatterbraind >>

There's not enough talk of Howl in this discussion. If we're talking about the ideal scenario for a PC paladin, let's talk about the same thing for the demilich - it could literally fly from around a corner, Howl in the middle of a high level party, and TPK it before anyone gets a turn. Game over, just like that.

Yes, a high-level party will likely have ways to mitigate that scenario and 15 is not a particularly challenging DC (but it is still fail-able by everyone). But how do you measure the threat level of something like that? 5e has mostly done away with such extreme save-or-suck effects, and when it tries to incorporate them it's not surprising that their math would break down.

I mean CR is a garbage metric anyway - especially at high levels - but this monster isn't rated particularly worse than others in my mind. It's just a glass cannon. My only experience with it in play was in a fight with several other creatures, and it was an effective and terrifying part of the encounter.

 Added to that the fact that those who aren't dropped by the howl outright are automatically frightened (unless immune, of course), which means that their attacks would be at disadvantage against the thing for their next turn.  As a DM I'd play the thing like this:

Pre-combat:  use the creatures truesight and massive intelligence score to sus out the spellcaster/nova strikers

1st turn (if not the DL):  Use a legendary action to fly up 15 feet (get out of melee range of the nova strikers)

1st lair action:  either drop the antimagic on a spellcaster or paladin, or (if none or they don't seem like the most prominent threat) use the lair shake to drop everyone prone for a nice howling

1st DL turn:  move into position to catch as many party members as possible and howl

Legendary actions:  use energy drain or vile curse depending on whether the first legendary action was spent to move

Then use the "no regain hitpoints" lair action next and Life Drain until howl recharges while keeping out of melee range.

I feel like the point here isn't even that the CR is wrong by the rules. For a long time it's been acknowledged that CR in general is pretty messed up. Not all, but there are a few (like the demilich) that stand out as particularly weirdly designed. The mummy lord is similarly flawed. It's a great monster, and one of my personal favorite statblocks in the game, but it only has 95 hp, and an AC 17. Add that to a vulnerability to fire damage, and this guy will get MELTED by any spellcaster of level 5 or higher really. It doesn't even require a crazy scenario. A fireball upcast even a little bit can one-shot it, as could probably any wildfire druid. The point is, CR is messed up, and trying to reason with it at this point isn't really the best option. Something my DM does (situationally) is max out the hp for the monsters we fight. Our party is level 7, and keep in mind that we all have magic items of some kind, but I would say that this is your best bet when trying to run a demilich or the like effectively. After all, you're the DM. It's your world. Your party just isn't going to have as much fun fighting the big boss when they can shred it because of CR so easily.

Quote from Solarsyphon >>

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.

 Honestly, I don't see that at all. Rogues are fun but damage dealing is not their primary ability.

Level 20 rogue does d8+10d6 +5 (assuming max stat) +3 (assuming a +3 weapon) = 4.5 + 35 +8 = 47.5 average damage. However, in this case the demilich is resistant to damage from magical weapons so they will only take 1/2 of that or about 24 points. A rogue gets only one sneak attack/turn. Even if the rogue somehow scored a crit (an assassin with surprise) the damage would be 2d8+20d6 +5 + 3 = 9+70+8 = 87 which would be halved to 43 by the demilich resistances.

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The best bet might be to grapple it and stuff it into a bag of devouring.

Was sent this thread's way by a friend, and I have to say I'm a little disappointed.

1.) Challenge Rating is a loose guesstimation at best and everybody knows it.  Half of running D&D is figuring out how to eyeball appropriate challenges for your specific party based on gut instinct and experience, because CR only gets you so far.  And the higher level your party gets, the less far CR goes.

2.) White room damage math is pointless.  No one is going to walk out of the inn after a nice refreshing long rest, wander over into a nearby flat wide-open farm field, and encounter a demilich just floating around.  This thing, if the party encounters it at all, is going to be at the bottom of a hellish trap-laden undead-infested tomb specifically designed to turn intruders into spare meat and tasty souls.  The whole "if a paladin rolls over 20 on initiative and then dumps all their spells into Smite it auto-wins!" thing is just ridiculous.  Even more ridiculous is assuming this will be every party's automatic default response to a demilich.

3.) The demilich is an ambush monster.  You find a bare, nekkid skull in the bottom of a monster-infested hellpit, and that skull doesn't do a damn thing unless you muss with it - at which point it's very likely most of the party ends up surprised and loses their first action.  If they do catch it before it acts, say with Divine Sense, then yes, they can get the drop on it.  Oh well.  Features working as intended.  If you don't Divine Sense it, and it's quite possible any palladalladingdongs in the party will have exhausted their Divine Senses by the time they get to the demilich's chamber, then the first they should generally know of the demilich's existence is the phrase "All right, I need everybody to roll initiative."

4.) "Only 80 HP" is a totally misleading statement.  The demilich has resistance to magical weapons, flat-out immunity to mundane weapons, and takes half damage at best from any saving-throw spell.  Only spell attacks get through unresisted, and high-level spell attacks basically don't exist.  It's also flat-out immune to most disabling conditions, which means its legendary resistances can be saved to avoid damage from big-punch spells rather than avoiding shit like Hold Monster or a monk's Stunning Strike.  The critter can absorb or avoid punishment well beyond what "only 80 HP" would suggest, especially given its small size and flight capability.  It can occupy nooks and holes that players simply can't get into or otherwise use flight to avoid a lot of melee nonsense.

5.) It's offensively mediocre, yes...until somebody fails a save against Howl.  Even one failed save is an emergency, which makes fighting the demilich tense and unpredictable.  At any point it can instantly down one or more players out of the blue, totally ignoring most any defense save Death Ward-style effects.  Are the chances of falling to Howl rleatively low in Tier 3?  Yes - but they ain't zero.

Does the critter merit CR 18?  Who knows, who cares.  Challenge rating is a fabrication anyways.  The prevailing attitude of "this thing is a garbage monster that any random set of level five yaybos can just flatten without effort" is ridiculous.  I would argue that if you're a DM and you run a demilich fight where the party flattens your demilich in one round before it can act?

Either the dice gods spoke and it was just the way things do in D&D sometimes, or you really suck at setting up a demilich encounter.

IS nobody going to talk about the phylactery and the demi lich's ability to become a lich after absorbing 1 soul?  I mean free revival should bump up cr by at least 1 or 2 at a minimum and the ability to turn into a cr 21 creature  after killing JUST 1 party member would account for the rest of the cr

Quote from AntonSirius >>

Quote from MalignantUndertone >>

Quote from Solarsyphon >>

I also just noticed this on the demi lich stat block:

Undead Nature. A demilich doesn’t require air, food, drink, or sleep. So great is a demilich’s will to survive that it always has the maximum number of hit points for its Hit Dice, instead of average hit points.

It has 128 hit points not 80. Its just got a weirdly designed stat block. That's about 400 effective hp if you don't have a way around it's defenses.

 

The stat block for Demilich states Hit Points: 80 (20d4).

80 HP makes more sense than 128 HP. Unless I'm missing something...

 

It's 80 (32d4) in the stat block

Apparently my MM is outdated.

Quote from MalignantUndertone >>

Quote from AntonSirius >>

Quote from MalignantUndertone >>

Quote from Solarsyphon >>

I also just noticed this on the demi lich stat block:

Undead Nature. A demilich doesn’t require air, food, drink, or sleep. So great is a demilich’s will to survive that it always has the maximum number of hit points for its Hit Dice, instead of average hit points.

It has 128 hit points not 80. Its just got a weirdly designed stat block. That's about 400 effective hp if you don't have a way around it's defenses.

 

The stat block for Demilich states Hit Points: 80 (20d4).

80 HP makes more sense than 128 HP. Unless I'm missing something...

 

It's 80 (32d4) in the stat block

 

Apparently my MM is outdated.

No, your Monster Manual is fine. I checked, and the demilich has never had its hit dice changed in an errata document. Hilariously, it seems that D&D Beyond's monster stat block code is so god-awful that it cannot display anything but average hit points, so they incorrectly gave it 32 hit dice instead of 20 so that its hit points would be the correct value.

Quote from SagaTympana >>

No, your Monster Manual is fine. I checked, and the demilich has never had its hit dice changed in an errata document. Hilariously, it seems that D&D Beyond's monster stat block code is so god-awful that it cannot display anything but average hit points, so they incorrectly gave it 32 hit dice instead of 20 so that its hit points would be the correct value.

 Custom monsters are totally able to do it. Possibly a bug in an early version of the code which they patched around.

They changed the dice in 2018 so it's average is 80 but forgot to change undead nature in the errata.  So it seems intended now that demilichs have  32-128 hit points average 80 instead of always 80 but because they didn't change undead nature on dnd beyond it says they have 128.  Since even though you usually use average specific > general and the undead nature would override it. 
https://media.wizards.com/2018/dnd/downloads/MM-Errata.pdf 

+1 for the whole "this creature is meh because it is beaten by this specific character" argument being a load of tripe.

Yes, if the demilich with antimagic is facing a party of paladins whose abilities bypass the 'lichs abilities, then yes, the demilich is going to die. But if it is facing a party with an artificer, a ranger, a fighter and a wizard, then things matter. antimagic renders most of the party ineffective.

Every creature has a weakness. You might as well say "trolls are weak because if the party uses fire then they will beat it", or "Tarrasques are weak because if the party can fly, they can beat it", or "Vampires suck because if the party fights them in daylght outside then they will beat them".

For a project I once tried to put every creature in the monster manual through the CR calculator from the DMG.

According to my notes; the Demilich has an offensive CR of 10 and a defensive CR of 22 giving an overall CR of 16. The official CR is 18, so there's not much between them.

The defensive CR is so high because of the Demilich's; immunities, legendary resistances, saving throws, Life drain attack and Avoidance. It's offensive CR is relatively low because it doesn't do much damage for the CR given, however the DMG method doesn't account for attacks that can instakill, which might be why it's lower. 

Quote from Sergeant_Garlic >>

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.

Have fun grinding them!

 things that will never happen for 300 pls

Quote from Alaphas >>

Quote from Sergeant_Garlic >>

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.

Have fun grinding them!

 things that will never happen for 300 pls

 Yeah, any fight plan that requires an empty salt pan is on the same level as a plan that requires the enemy to only roll 1s.

 I mean, there's way more kitable monsters than a demilich. The classic for this is the first level aarakokra cleric taking down the Tarrasque by spamming Sacred Flame.

Quote from Pantagruel666 >>

 I mean, there's way more kitable monsters than a demilich. The classic for this is the first level aarakokra cleric taking down the Tarrasque by spamming Sacred Flame.

 And that will never ever work in my game. I thank God that I was around for the 1e version. Same with demilich.

Quote from Wysperra >>

Quote from Pantagruel666 >>

 I mean, there's way more kitable monsters than a demilich. The classic for this is the first level aarakokra cleric taking down the Tarrasque by spamming Sacred Flame.

 And that will never ever work in my game. I thank God that I was around for the 1e version. Same with demilich.

In 1e about the earliest you could cheese the Tarrasque was level 7 (because no-save fear), but it had the same problem of zero ability to deal with flying opponents. The only edition that actually had a method of dealing with fliers was 4e, though the 3.5e version was durable enough that it could just ignore the buzzing flies of low to mid level characters.

Quote from Pantagruel666 >>

 I mean, there's way more kitable monsters than a demilich. The classic for this is the first level aarakokra cleric taking down the Tarrasque by spamming Sacred Flame.

This is why they should have gone full Godzilla with it and given it a breath weapon