What CR is this monster?

[Oramac]

So last night for story reasons I had to create a Fire Giant Spellcaster on the fly. I took the base fire giant and added the spellcasting of the Mage (MM pg. 347), and I increased the save DC from 14 up to 16.

My players are usually pretty damn good tactically, and outside of a couple bad decisions on their part, this felt about right for the group. The whole fight was this giant, a regular fire giant, and a fire giant "youngling" (half-ogre with fire immunity).

What CR would you say this NPC is?

[Unoriginal]

If you simply gave them the Mage's spellcasting without increasing their HDs or modifying the spell list, this Fire Giant Spellcaster's CR was 9, same as a regular Fire Giant. Arguably 10.

The Mage's spell list doesn't really improve the giant's damage output or resistance in a way that affect the CR.

[Oramac]

If you simply gave them the Mage's spellcasting without increasing their HDs or modifying the spell list, this Fire Giant Spellcaster's CR was 9, same as a regular Fire Giant. Arguably 10.

The Mage's spell list doesn't really improve the giant's damage output or resistance in a way that affect the CR.

Good to know. Thanks!

[Louro]

The Mage's spell list doesn't really improve the giant's damage output or resistance in a way that affect the CR.
Yes it does, if he casts a fireball. With a 16 DC that's a hell of damages, potentially to everyone.

[Oramac]

Yes it does, if he casts a fireball. With a 16 DC that's a hell of damages, potentially to everyone.

This is pretty much what happened. My players stupidly stayed clumped together, so the Caster just kept lobbing up-cast Fireballs at them. (It didn't make sense to me for a Fire Giant to cast Cone of Cold)

[Unoriginal]

Yes it does, if he casts a fireball. With a 16 DC that's a hell of damages, potentially to everyone.

That's 8d6 of damage, for an average of 24 damages per round. While it being able to hit a lot of person is impressive, a normal Fire Giant can do two attacks for 6d6+7 damages, average 28, per round.

All in all Fireball is not enough damages to increase the CR that significantly.


This is pretty much what happened. My players stupidly stayed clumped together, so the Caster just kept lobbing up-cast Fireballs at them. (It didn't make sense to me for a Fire Giant to cast Cone of Cold)

Cone of Cold is useful when you deal with people immune to fire. Like other Fire Giants.

[Oramac]

Cone of Cold is useful when you deal with people immune to fire. Like other Fire Giants.

True. But when it's the Fire Giant casting it, it doesn't make sense for them to have. A Fire Giant casting Fireball into a group of melee combatants that includes other Fire Giants doesn't have to worry about friendly fire, which is what happened in this case.

[JackPhoenix]

Cone of Cold is useful when you deal with people immune to fire. Like other Fire Giants.

Indeed. It makes less sense to use spells most creature you meet are immune or resistant to. There are some advantages... you can be less discriminate with AoE against other foes... but that Fireball won't help you against rival fire giant, or if your pet hellhounds get loose, or when a red dragon decides he likes your volcanic home and your shinies. Or if the outside attackers prepare themselves to fight fire giants by obtaining source of fire resistance.

[Louro]

That's 8d6 of damage, for an average of 24 damages per round. While it being able to hit a lot of person is impressive, a normal Fire Giant can do two attacks for 6d6+7 damages, average 28, per round.

All in all Fireball is not enough damages to increase the CR that significantly.

24 per player hit. Which being inmune to fire means all melee attackers at the very least. That's scary as hell.
Such power of spellcasting increases the challenge of any monster. Don't account only for damage, but also for utility. You are adding 5 levels of wizardry. That's RAW power.

[Unoriginal]

24 per player hit. Which being inmune to fire means all melee attackers at the very least. That's scary as hell.

Yes, it's impressive. Still not enough to bump the CR by more than 1.

Fire Giants hits like trains already.



Such power of spellcasting increases the challenge of any monster.

No, it doesn't.


Don't account only for damage, but also for utility.

Not something that is calculated by CR, though.




You are adding 5 levels of wizardry. That's RAW power.

Which is powerful, but given we're talking about a Fire Giant, it's more a lateral move.

Yes, they could use Greater Invisibility to gain advantage and get harder to hit, but that has action cost and concentration. Which diminishes their damage output for the first 3 rounds.

Yes, Fireball is impressive, but not enough compared for the Fire Giant's regular attack to be a huge power boost.

Etc.

If the Giant had time to prepare an ambush or the like, it'd be a much more difficult encounter than the CR indicates. But that's not how CR work, nor is it what it's used for.

[Louro]

Remember the manual warns you about such things. When you calculate an encounter you need to aknwoledge for the whole situation. And that particular fireball is a big situation.
Like being able to open combat in the first round hitting the whole party for a good chunk of damages.

[Unoriginal]

Remember the manual warns you about such things. When you calculate an encounter you need to aknwoledge for the whole situation. And that particular fireball is a big situation.
Like being able to open combat in the first round hitting the whole party for a good chunk of damages.

True. CR is at best only the beginning of encounter building, if even that.

Point is, OP asked for the CR, not for the encounter as a whole.

In any case, it seems like a fun encounter. Always nice when the enemies have the time to show what they can do.

[dreast]

CR of spells has to factor in multiple targets (generally 2 is assumed). Thus, you have to multiply by at least 2 the average damage of that fireball each of the 3 rounds where he could cast it. You would be justified in multiplying by 3 if all creatures on the FG’s side are immune to fire, since it has a huge radius and no downside.

[MoiMagnus]

CR of spells has to factor in multiple targets (generally 2 is assumed). Thus, you have to multiply by at least 2 the average damage of that fireball each of the 3 rounds where he could cast it. You would be justified in multiplying by 3 if all creatures on the FG’s side are immune to fire, since it has a huge radius and no downside.

Depends on the size of the party.
In a 4 party group, that's not unlikely that you will just never be able to target more than 2 peoples with a fireball. Unless the terrain force you into being near each others. But then, that's not something to count in the CR of the monster, that's just a combo terrain/monster.

[Oramac]

Yes, they could use Greater Invisibility to gain advantage and get harder to hit, but that has action cost and concentration. Which diminishes their damage output for the first 3 rounds.

If the Giant had time to prepare an ambush or the like, it'd be a much more difficult encounter than the CR indicates. But that's not how CR work, nor is it what it's used for.


Remember the manual warns you about such things. When you calculate an encounter you need to aknwoledge for the whole situation. And that particular fireball is a big situation.
Like being able to open combat in the first round hitting the whole party for a good chunk of damages.


In any case, it seems like a fun encounter. Always nice when the enemies have the time to show what they can do.

It's interesting you all bring these points up, as this is more or less exactly what happened.

=====================

All 8th Level
Eldritch Knight
Bard/Warlock
Draconic Sorcerer
Open Hand Monk
Divine Soul Sorcerer
War Cleric

The party decided to take a long rest inside the Fire Giant base, after having killed 2 FG's, 2 Hell Hounds, and a Drow. They did not clean up the bodies or anything.

Each of the 3 players on watch saw a different FG patrol go by, the last of which was the spellcaster, who made her perception check against the PC's stealth check. Instead of attacking, she set up an ambush in the next room.

The spellcaster FG (semi-hiding against a wall around a corner) cast Greater Invisibility on herself as soon as she saw a PC coming down the hallway. I gave the PC a perception check to see her before the spell took effect, which the PC failed miserably.

The regular FG's ran up to the PC's, choking off the hallway and keeping most of them trapped in the hallway, lest they risk an Opportunity Attack from the regular FG.

And then the spellcaster started chucking fireballs into the hallway indiscriminately, since she didn't have to worry about hurting her allies at all.

It was a rather interesting fight, since both Sorcerers Twinned Greater Invis on their allies as well. So only 4 of the 9 combatants on the field were actually visible.

[Unoriginal]

Why didn't the spellcaster raise the alarm and get everyone who was still alive up to the PCs to kill them before they finish their rest?

[Oramac]

Why didn't the spellcaster raise the alarm and get everyone who was still alive up to the PCs to kill them before they finish their rest?

Because the PC's had already killed everyone else. I think they got a little overconfident with resting in the base proper instead of retreating like they had been doing.

[Plantae]

Adding the spellcasting from the Mage absolutely doesn't necessarily increase the Fire Giant's offensive CR, which is already CR 10 based on damage output and attack bonus. Even using fireball effectively, and assuming at least two targets (which the CR calculations in the DMG recommend), the damage/DC doesn't exceed this. In the scenario depicted, the Fire Giant used fireball very effectively, but a monster's CR exists in a vacuum.

I'd argue it does increase the Fire Giant's defensive CR, however. Greater invisibility is hugely effective against unprepared PCs, but one could certainly argue about the sunk action cost. But even ignoring that, shield can be cast repeatedly by the Fire Giant mage, raising it's effective AC to 23 in any round where it doesn't need to do something else with its reaction. This reduces potential damage output from opportunity attacks perhaps, but the offensive CR doesn't account for that in the first place.