Just looking for some brainstorming ideas that I may not have considered.
Setup: Well, this is a first. In the campaign, I'm running I have a Wizard who is in love with his Fireball spell, a Warlock who cannot get enough of the Shatter spell, and a Ranger who finds his Hail of Thorns nifty.
I cannot fault them for using these spells on an ongoing basis as they seem to find opportunities to cast them all in the same round and that's on the encounters as they occur. The problem is where the fights should be challenging these three characters, out of a party of five, just tears right through the enemy as they are tissue on top of the fact they are taking the fun out of the game for the other two players who don't really get much to do.
Plus as a DM I'm seeing the combats have not been that enjoyable or engaging.
One of the things I've thought of to counter this, Up the Hit Points so all the enemies can take this AOE damage and still be standing. This seems like a low-hanging fruit idea but the simple solution may make the best result.
Another idea is up the saving throws bonuses so the creature still takes damage but at least in favor of half damage. I'm not in love with this one as it really takes away from the player spell more than should just to balance out one-sided combat.
I can drop Anti-Magic zones but how can I justify every cave or dwelling that continually has one of those which result in neutering the spell casters.
Question: Besides Anit-Magic fields, Saving Throw, or HP increase, what other ways to challenge the party and not completely neuter three players because they are very attached to high dps spells for encounters.
That and have the players do multiple fights per day. If they are burning that many resources then they cant sustain that. more hp as well isnt an awful idea. Doesn't make them useless, they just have to use their resources more wisely
I don't know if you use a grid and minis but positioning can be a HUGE discourager to AoE spells. If your enemies get higher initiatives, have them position themselves so they're not clustered. Or have them intermingled with the party so that friendly fire becomes an issue.
I play as a fireball loving wizard in one campaign, and I gotta say, fireball loses priority very quickly after the first round if im forced to pick between using a whole spell slot for 1 enemy, or hitting my party
Spread out your enemies more, have the party get surrounded when enemies ambush them, or during battles have enemies position themselves behind the characters. Use more enemies with ranged attacks as well. If you play your enemies smart, and they know the party have these AOE abilities, have them adjust their tactics accordingly.
Spread out your enemies more, have the party get surrounded when enemies ambush them, or during battles have enemies position themselves behind the characters. Use more enemies with ranged attacks as well. If you play your enemies smart, and they know the party have these AOE abilities, have them adjust their tactics accordingly.
I don't know if you use a grid and minis but positioning can be a HUGE discourager to AoE spells. If your enemies get higher initiatives, have them position themselves so they're not clustered. Or have them intermingled with the party so that friendly fire becomes an issue.
I play as a fireball loving wizard in one campaign, and I gotta say, fireball loses priority very quickly after the first round if im forced to pick between using a whole spell slot for 1 enemy, or hitting my party
This.^^^
I don’t use a grid, but I narrate it this way without the grid and it has the same effect.
They’ll just have to learn to not wait for that one perfect triple kablam and adapt their expectations to maybe only catching smaller groups when they can.
But you don’t want to overdo it, if they never get to blow the 9 hells out of a solid group of baddies then that sucks for them.
Question: Besides Anit-Magic fields, Saving Throw, or HP increase, what other ways to challenge the party and not completely neuter three players because they are very attached to high dps spells for encounters.
Run more encounters per day. Use bad guys that are separated by significant distances or heavy cover (trench warfare actually makes a bit of sense in D&D...).
In addition to spreading enemies out (and don’t forget all dimensions —have some fly with others on the ground), put them in tighter spaces. Use smaller rooms so big AoEs will have to impact the party. Have a target backed against a wall so the wizard can’t put the fireball 20’ behind it. Place enemies around corners. Fireball spreads around corners, but if the caster doesn’t see the enemy, they won’t know just where to target.
I actually think this is a case of not seeing the wood for the trees. The problem has little to do with AoE spells, and more to do with the bizarrely low hit points involved in monster scaling, and I'm guessing that since Shatter is still a relevant damage source, your characters have just hit level 5.
First up, level 5 is the biggest power jump in the game. It's basically like your characters doubled in level. What was threatening at level 4 is now irrelevant, and instead of going from CR5 creatures to CR6, you need to go up to CR8 and above to give decent encounters.
But second, monster hit points are just daft (and if you have a party of more than 4, you should be applying multipliers anyway). My current party have just reached level 5. The Bloodhunter has +8 to hit with his crossbow expert shooting, and when he Hexes he deals 1d10+4+d6+d6 damage (average 15 damage per shot). The wild magic barbarian, with a +1 Maul, using Great Weapon Master has +3 to hit but Advantage, and deals 2d6+5+10 damage, averaging 22 damage per hit. Compare these damage outputs, with 2 attacks each, to the hit points of a mighty CR13 Beholder. The Beholder has 180 hit points, and AC18. Each of these characters is likely to hit the beholder once per turn (let's ignore crits for now) with their 2 attacks, averaging 38 damage between them. Our friend the CR13 beholder dies to 2 x level 5 characters in about 5 turns on average, as long as it's not shooting them.
This is absolutely nuts!
If 4 of these guys get up in its face with a surprise round, then the beholder is likely to suffer 76 damage initially, then the same in round 1 leaving it having suffered 152 damage out of 180 hit points. With a surprise round, the beholder dies in the second round of combat to a party of 4 level 5 characters. If this all sounds implausible (the beholder would zap them all!) then let's scale it back to see that a CR5 Hill Giant is likely to take 6-7 attacks from a party of 4 level 5 characters and die in a single turn.
By the time your characters have access to Fireball, creatures like CR1 Orcs are basically irrelevant. My players, who have only a handful of +1 items, can easily handle 15 of them at once.
So your issue is basically being multiplied by players using lots of spells simultaneously. Fireball itself isn't all that impressive as single target damage (see the 2 attacks, average 22 damage a hit barbarian above) and is likely to be saved by tough enemies, dealing only an average of 14 damage per hit which is pretty weak. Shatter damage is pretty weak too which is why I'm assuming your guys just hit 5.
So anyway, to make encounters cool and fun you need to do more than just have a stand up fight against some monsters that run at them (the 'Patchwerk' style). Here are some of the encounters coming up in my campaign:
6 x level 5 characters against a Stone Golem with 3 Legendary actions and maxed hit points (235hp), who animates the CR3 statues around the map as one of those actions, and has a lazer eye ray to hit the back line. This means the enemies rise up gradually, splitting party focus between the boss and the minions.
Hold an area against waves of creatures that emerge from 3 portals. The minions are either a big guy (hill giant stats), 3 small ones (orc stats), a spitting one (ogre stats with ranged attack), or one that runs at you and explodes. All their movement is reduced to 20 feet, and they come from 3 different directions; players need to hold out for 9 turns as more and more adds spawn in.
Fight on an airship against 3 red dragon wyrmlings and a warlock on a flying carpet. They need to douse fires and keep the airship from going down as much as they have to fight the enemies.
A battle within a claustrophobic ship cabin against a level 13 psi warrior and a kraken priest. The goal is to stop them escaping, which they will be attempting to do.
A long bridge across lava occupied by duergar. At the opposite end is a huge duergar war machine (like a mech) that fires cannons. Players will do better if they can close the 240 feet distance before engaging it.
An encounter with an Annis Hag posing as an old woman. The players are led there by 2 small children, corrupted by the hag. The Hag repeatedly disguises herself as one of the children, leading to the PCs not known whether it's the hag or otherwise. Meanwhile they're being attacked by Meenlocks, which buy her time.
So in summary:
1. Your PCs just got to 5, so they're OP for the usual monsters 2. Up the hit points of most monsters to maximum to make them more challenging 3. Vary encounters so that 2 of 3 fifights have an interesting gimmick (the occasional slug-fest is fun!)
I actually think this is a case of not seeing the wood for the trees. The problem has little to do with AoE spells, and more to do with the bizarrely low hit points involved in monster scaling, and I'm guessing that since Shatter is still a relevant damage source, your characters have just hit level 5.
First up, level 5 is the biggest power jump in the game. It's basically like your characters doubled in level. What was threatening at level 4 is now irrelevant, and instead of going from CR5 creatures to CR6, you need to go up to CR8 and above to give decent encounters.
But second, monster hit points are just daft (and if you have a party of more than 4, you should be applying multipliers anyway). My current party have just reached level 5. The Bloodhunter has +8 to hit with his crossbow expert shooting, and when he Hexes he deals 1d10+4+d6+d6 damage (average 15 damage per shot). The wild magic barbarian, with a +1 Maul, using Great Weapon Master has +3 to hit but Advantage, and deals 2d6+5+10 damage, averaging 22 damage per hit. Compare these damage outputs, with 2 attacks each, to the hit points of a mighty CR13 Beholder. The Beholder has 180 hit points, and AC18. Each of these characters is likely to hit the beholder once per turn (let's ignore crits for now) with their 2 attacks, averaging 38 damage between them. Our friend the CR13 beholder dies to 2 x level 5 characters in about 5 turns on average, as long as it's not shooting them.
This is absolutely nuts!
If 4 of these guys get up in its face with a surprise round, then the beholder is likely to suffer 76 damage initially, then the same in round 1 leaving it having suffered 152 damage out of 180 hit points. With a surprise round, the beholder dies in the second round of combat to a party of 4 level 5 characters. If this all sounds implausible (the beholder would zap them all!) then let's scale it back to see that a CR5 Hill Giant is likely to take 6-7 attacks from a party of 4 level 5 characters and die in a single turn.
By the time your characters have access to Fireball, creatures like CR1 Orcs are basically irrelevant. My players, who have only a handful of +1 items, can easily handle 15 of them at once.
So your issue is basically being multiplied by players using lots of spells simultaneously. Fireball itself isn't all that impressive as single target damage (see the 2 attacks, average 22 damage a hit barbarian above) and is likely to be saved by tough enemies, dealing only an average of 14 damage per hit which is pretty weak. Shatter damage is pretty weak too which is why I'm assuming your guys just hit 5.
So anyway, to make encounters cool and fun you need to do more than just have a stand up fight against some monsters that run at them (the 'Patchwerk' style). Here are some of the encounters coming up in my campaign:
6 x level 5 characters against a Stone Golem with 3 Legendary actions and maxed hit points (235hp), who animates the CR3 statues around the map as one of those actions, and has a lazer eye ray to hit the back line. This means the enemies rise up gradually, splitting party focus between the boss and the minions.
Hold an area against waves of creatures that emerge from 3 portals. The minions are either a big guy (hill giant stats), 3 small ones (orc stats), a spitting one (ogre stats with ranged attack), or one that runs at you and explodes. All their movement is reduced to 20 feet, and they come from 3 different directions; players need to hold out for 9 turns as more and more adds spawn in.
Fight on an airship against 3 red dragon wyrmlings and a warlock on a flying carpet. They need to douse fires and keep the airship from going down as much as they have to fight the enemies.
A battle within a claustrophobic ship cabin against a level 13 psi warrior and a kraken priest. The goal is to stop them escaping, which they will be attempting to do.
A long bridge across lava occupied by duergar. At the opposite end is a huge duergar war machine (like a mech) that fires cannons. Players will do better if they can close the 240 feet distance before engaging it.
An encounter with an Annis Hag posing as an old woman. The players are led there by 2 small children, corrupted by the hag. The Hag repeatedly disguises herself as one of the children, leading to the PCs not known whether it's the hag or otherwise. Meanwhile they're being attacked by Meenlocks, which buy her time.
So in summary:
1. Your PCs just got to 5, so they're OP for the usual monsters 2. Up the hit points of most monsters to maximum to make them more challenging 3. Vary encounters so that 2 of 3 fifights have an interesting gimmick (the occasional slug-fest is fun!)
Thank you for the advice. You are correct they just hit 5th level and I am seeing the power jump significantly. So it looks like I'm not adjusting accordingly or trying too hard to use the DDB Encounter tool to generate and gauge my combat challenges.
That and have the players do multiple fights per day. If they are burning that many resources then they cant sustain that. more hp as well isnt an awful idea. Doesn't make them useless, they just have to use their resources more wisely
In the latest session, the party went through three combats but had one opportunity for a Short Rest which the wizard was able to use Arcane Recovery (he's 5th level) to get a spell slot back for his Fireball.
I don't know if you use a grid and minis but positioning can be a HUGE discourager to AoE spells. If your enemies get higher initiatives, have them position themselves so they're not clustered. Or have them intermingled with the party so that friendly fire becomes an issue.
I play as a fireball loving wizard in one campaign, and I gotta say, fireball loses priority very quickly after the first round if im forced to pick between using a whole spell slot for 1 enemy, or hitting my party
Roll20 and I have been spacing the enemy out at much as I can to avoid these spells but turn out a 20-foot circle for fireball were still enough to take down five of the creatures. This is on me I know, but it was worth clarifying how the encounters are ran.
It depends on the level, but monsters start getting resistances to things in particular fire when they get higher CRs, this should take care of the fireball. The other two don't have huge resistances to but also have smaller areas of effect, so maybe not bundle the adversaries, of make them seek contact with the PCs ?
5th level and what could be the issue reading through all the comments and taking the feedback is yeah, I have creatures with decently high CR's, using the DDB Encounter tool, for the narrative of what I want the party to encounter but I'm just not hitting the mark while I think the encounter is challenging I'm still not close to making it so
I don't know if you use a grid and minis but positioning can be a HUGE discourager to AoE spells. If your enemies get higher initiatives, have them position themselves so they're not clustered. Or have them intermingled with the party so that friendly fire becomes an issue.
I play as a fireball loving wizard in one campaign, and I gotta say, fireball loses priority very quickly after the first round if im forced to pick between using a whole spell slot for 1 enemy, or hitting my party
This.^^^
I don’t use a grid, but I narrate it this way without the grid and it has the same effect.
They’ll just have to learn to not wait for that one perfect triple kablam and adapt their expectations to maybe only catching smaller groups when they can.
But you don’t want to overdo it, if they never get to blow the 9 hells out of a solid group of baddies then that sucks for them.
I do use grid and try my best to spread things out but it could be my rooms are just not big enough to get a spread but small enough for my players to be efficient.
Question: Besides Anit-Magic fields, Saving Throw, or HP increase, what other ways to challenge the party and not completely neuter three players because they are very attached to high dps spells for encounters.
Run more encounters per day. Use bad guys that are separated by significant distances or heavy cover (trench warfare actually makes a bit of sense in D&D...).
They went through three encounters but I got dinged on a short rest that I could not say no to or able to put in some random encounter.
In addition to spreading enemies out (and don’t forget all dimensions —have some fly with others on the ground), put them in tighter spaces. Use smaller rooms so big AoEs will have to impact the party. Have a target backed against a wall so the wizard can’t put the fireball 20’ behind it. Place enemies around corners. Fireball spreads around corners, but if the caster doesn’t see the enemy, they won’t know just where to target.
Fire resistance is pretty common.
Counterspell.
The wizard is School of Evocation and he leverages "Sculpt Spells" ability when it comes to close quarters casting of Fireball. The Warlock sometimes will keep his spell in check if the room is small enough.
If your PCs are even slightly optimised and you are having them have just a few encounters each day, they should all be deadly, and don't use low CRs in there, that's all.
I've been trying to follow the daily XP Thresholds listed in the DMG along with the DDB Encounter tool so I 'thought' I was properly balancing my encounters. I may look at this party and hit a constant Deadly to see how things play out but also manage to not give a TPK scenario.
If your PCs are even slightly optimised and you are having them have just a few encounters each day, they should all be deadly, and don't use low CRs in there, that's all.
I've been trying to follow the daily XP Thresholds listed in the DMG along with the DDB Encounter tool so I 'thought' I was properly balancing my encounters. I may look at this party and hit a constant Deadly to see how things play out but also manage to not give a TPK scenerio.
Balancing encounters is something of a trial and error. The more you do it, the more you'll learn what "feels right" for a given party. And remember while your learning, If you start completely wrecking your party because of a misbalance, YOU'RE the DM! Unless you roll in the open, they have NO CLUE if you rolled a 7 or a 17. And before someone gets in saying "But you shouldn't fudge your rolls! it takes the challenge out and PC's should live with consequences!" That's not what I'm talking about. I'm talking about a DM realizing they balanced the encounter horribly wrong and wants to ensure that THEIR mistake doesn't TPK the party
In addition to spreading enemies out (and don’t forget all dimensions —have some fly with others on the ground), put them in tighter spaces. Use smaller rooms so big AoEs will have to impact the party. Have a target backed against a wall so the wizard can’t put the fireball 20’ behind it. Place enemies around corners. Fireball spreads around corners, but if the caster doesn’t see the enemy, they won’t know just where to target.
Fire resistance is pretty common.
Counterspell.
The wizard is School of Evocation and he leverages "Sculpt Spells" ability when it comes to close quarters casting of Fireball. The Warlock sometimes will keep his spell in check if the room is small enough.
Also remember - this guy specifically set his build up to be able to do evocation spells, so this is going to be the norm for combat. Let him have a bit of fun!
Just make sure to throw in some res-fire opponents and you’ll entice him to try different AOE spells to mix it up.
More encounters per day, some good spacing, res-spell res-fire creatures… you’ll find it’ll stay interesting. Also, once the baddies are smarter they should be swarming that AOE spammer strategically. This will give your other PCs something to do.
Since you are using grids, are you using the DMG optional rule for diagonals, so that you have a circular shape to your fireball?
It allows more realistic distances to be measured for diagonals, and ends up with circular areas of damage for fireballs instead of simply covering a 40 x 40 ft square!
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Just looking for some brainstorming ideas that I may not have considered.
Setup: Well, this is a first. In the campaign, I'm running I have a Wizard who is in love with his Fireball spell, a Warlock who cannot get enough of the Shatter spell, and a Ranger who finds his Hail of Thorns nifty.
I cannot fault them for using these spells on an ongoing basis as they seem to find opportunities to cast them all in the same round and that's on the encounters as they occur. The problem is where the fights should be challenging these three characters, out of a party of five, just tears right through the enemy as they are tissue on top of the fact they are taking the fun out of the game for the other two players who don't really get much to do.
Plus as a DM I'm seeing the combats have not been that enjoyable or engaging.
One of the things I've thought of to counter this, Up the Hit Points so all the enemies can take this AOE damage and still be standing. This seems like a low-hanging fruit idea but the simple solution may make the best result.
Another idea is up the saving throws bonuses so the creature still takes damage but at least in favor of half damage. I'm not in love with this one as it really takes away from the player spell more than should just to balance out one-sided combat.
I can drop Anti-Magic zones but how can I justify every cave or dwelling that continually has one of those which result in neutering the spell casters.
Question: Besides Anit-Magic fields, Saving Throw, or HP increase, what other ways to challenge the party and not completely neuter three players because they are very attached to high dps spells for encounters.
That and have the players do multiple fights per day. If they are burning that many resources then they cant sustain that. more hp as well isnt an awful idea. Doesn't make them useless, they just have to use their resources more wisely
I exist, and I guess so does this
I don't know if you use a grid and minis but positioning can be a HUGE discourager to AoE spells. If your enemies get higher initiatives, have them position themselves so they're not clustered. Or have them intermingled with the party so that friendly fire becomes an issue.
I play as a fireball loving wizard in one campaign, and I gotta say, fireball loses priority very quickly after the first round if im forced to pick between using a whole spell slot for 1 enemy, or hitting my party
Spread out your enemies more, have the party get surrounded when enemies ambush them, or during battles have enemies position themselves behind the characters. Use more enemies with ranged attacks as well. If you play your enemies smart, and they know the party have these AOE abilities, have them adjust their tactics accordingly.
Spread out your enemies more, have the party get surrounded when enemies ambush them, or during battles have enemies position themselves behind the characters. Use more enemies with ranged attacks as well. If you play your enemies smart, and they know the party have these AOE abilities, have them adjust their tactics accordingly.
This.^^^
I don’t use a grid, but I narrate it this way without the grid and it has the same effect.
They’ll just have to learn to not wait for that one perfect triple kablam and adapt their expectations to maybe only catching smaller groups when they can.
But you don’t want to overdo it, if they never get to blow the 9 hells out of a solid group of baddies then that sucks for them.
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Run more encounters per day. Use bad guys that are separated by significant distances or heavy cover (trench warfare actually makes a bit of sense in D&D...).
In addition to spreading enemies out (and don’t forget all dimensions —have some fly with others on the ground), put them in tighter spaces. Use smaller rooms so big AoEs will have to impact the party. Have a target backed against a wall so the wizard can’t put the fireball 20’ behind it. Place enemies around corners. Fireball spreads around corners, but if the caster doesn’t see the enemy, they won’t know just where to target.
Fire resistance is pretty common.
Counterspell.
I actually think this is a case of not seeing the wood for the trees. The problem has little to do with AoE spells, and more to do with the bizarrely low hit points involved in monster scaling, and I'm guessing that since Shatter is still a relevant damage source, your characters have just hit level 5.
First up, level 5 is the biggest power jump in the game. It's basically like your characters doubled in level. What was threatening at level 4 is now irrelevant, and instead of going from CR5 creatures to CR6, you need to go up to CR8 and above to give decent encounters.
But second, monster hit points are just daft (and if you have a party of more than 4, you should be applying multipliers anyway). My current party have just reached level 5. The Bloodhunter has +8 to hit with his crossbow expert shooting, and when he Hexes he deals 1d10+4+d6+d6 damage (average 15 damage per shot). The wild magic barbarian, with a +1 Maul, using Great Weapon Master has +3 to hit but Advantage, and deals 2d6+5+10 damage, averaging 22 damage per hit. Compare these damage outputs, with 2 attacks each, to the hit points of a mighty CR13 Beholder. The Beholder has 180 hit points, and AC18. Each of these characters is likely to hit the beholder once per turn (let's ignore crits for now) with their 2 attacks, averaging 38 damage between them. Our friend the CR13 beholder dies to 2 x level 5 characters in about 5 turns on average, as long as it's not shooting them.
This is absolutely nuts!
If 4 of these guys get up in its face with a surprise round, then the beholder is likely to suffer 76 damage initially, then the same in round 1 leaving it having suffered 152 damage out of 180 hit points. With a surprise round, the beholder dies in the second round of combat to a party of 4 level 5 characters. If this all sounds implausible (the beholder would zap them all!) then let's scale it back to see that a CR5 Hill Giant is likely to take 6-7 attacks from a party of 4 level 5 characters and die in a single turn.
By the time your characters have access to Fireball, creatures like CR1 Orcs are basically irrelevant. My players, who have only a handful of +1 items, can easily handle 15 of them at once.
So your issue is basically being multiplied by players using lots of spells simultaneously. Fireball itself isn't all that impressive as single target damage (see the 2 attacks, average 22 damage a hit barbarian above) and is likely to be saved by tough enemies, dealing only an average of 14 damage per hit which is pretty weak. Shatter damage is pretty weak too which is why I'm assuming your guys just hit 5.
So anyway, to make encounters cool and fun you need to do more than just have a stand up fight against some monsters that run at them (the 'Patchwerk' style). Here are some of the encounters coming up in my campaign:
So in summary:
1. Your PCs just got to 5, so they're OP for the usual monsters
2. Up the hit points of most monsters to maximum to make them more challenging
3. Vary encounters so that 2 of 3 fifights have an interesting gimmick (the occasional slug-fest is fun!)
Thank you for the advice. You are correct they just hit 5th level and I am seeing the power jump significantly. So it looks like I'm not adjusting accordingly or trying too hard to use the DDB Encounter tool to generate and gauge my combat challenges.
In the latest session, the party went through three combats but had one opportunity for a Short Rest which the wizard was able to use Arcane Recovery (he's 5th level) to get a spell slot back for his Fireball.
Roll20 and I have been spacing the enemy out at much as I can to avoid these spells but turn out a 20-foot circle for fireball were still enough to take down five of the creatures. This is on me I know, but it was worth clarifying how the encounters are ran.
5th level and what could be the issue reading through all the comments and taking the feedback is yeah, I have creatures with decently high CR's, using the DDB Encounter tool, for the narrative of what I want the party to encounter but I'm just not hitting the mark while I think the encounter is challenging I'm still not close to making it so
I do use grid and try my best to spread things out but it could be my rooms are just not big enough to get a spread but small enough for my players to be efficient.
They went through three encounters but I got dinged on a short rest that I could not say no to or able to put in some random encounter.
The wizard is School of Evocation and he leverages "Sculpt Spells" ability when it comes to close quarters casting of Fireball. The Warlock sometimes will keep his spell in check if the room is small enough.
I've been trying to follow the daily XP Thresholds listed in the DMG along with the DDB Encounter tool so I 'thought' I was properly balancing my encounters. I may look at this party and hit a constant Deadly to see how things play out but also manage to not give a TPK scenario.
Balancing encounters is something of a trial and error. The more you do it, the more you'll learn what "feels right" for a given party.
And remember while your learning, If you start completely wrecking your party because of a misbalance, YOU'RE the DM! Unless you roll in the open, they have NO CLUE if you rolled a 7 or a 17.
And before someone gets in saying "But you shouldn't fudge your rolls! it takes the challenge out and PC's should live with consequences!" That's not what I'm talking about. I'm talking about a DM realizing they balanced the encounter horribly wrong and wants to ensure that THEIR mistake doesn't TPK the party
Also remember - this guy specifically set his build up to be able to do evocation spells, so this is going to be the norm for combat. Let him have a bit of fun!
Just make sure to throw in some res-fire opponents and you’ll entice him to try different AOE spells to mix it up.
More encounters per day, some good spacing, res-spell res-fire creatures… you’ll find it’ll stay interesting. Also, once the baddies are smarter they should be swarming that AOE spammer strategically. This will give your other PCs something to do.
Since you are using grids, are you using the DMG optional rule for diagonals, so that you have a circular shape to your fireball?
It allows more realistic distances to be measured for diagonals, and ends up with circular areas of damage for fireballs instead of simply covering a 40 x 40 ft square!