D&D 5E Boss Fight Advice

[TaranTheWanderer]

As a finale of a campaign, one of the players is being transformed into a demon and will take on the party. It's supposed to be a fun 'what if'/alternate finish one-shot adventure but I need help balancing things.

The player is a minotaur barbarian with Polearm Master, Sentinel and Great Weapon Fighting.

What CR creature should I be looking at? The party is 13th.
A Paladin/sorcerer with incredibly high AC
A rogue/warlock/bard. Essentially some smiting and misty stepping with a touch of sneak attack
A tabaxi monk who specializes in stun locking and incredible movement (including mobility)
An straight divination wizard. Force wall, magic jar, teleport, telekinesis and some battlefield control spells.

We are thinking of just reskinning a demon Lord. There is a minotaur Demon Lord but he's CR 25 so I wonder if that might be too much.
I thought of reskinning a pit fiend. Replacing it's flight with a trample/shove ability, and reskinning some of its attacks and giving him some interesting legendary actions.

There will be a couple of encounters to wear down resources a bit, but not much. Also wondering if we should add some fodder to soak PC attacks since 1 vs 4 tends to be a slaughter.

Thoughts/ideas/comments?

 

[GuyBoy]

I'd definitely add some fodder. 1 v 4 is, as you say, likely to be a slaughter. Maybe some minotaur minions?

 

[prabe]

Minions, definitely minions. Go ahead and reskin Baphomet. Have fun--especially if this is a fight the PCs are looking for.

 

[TaranTheWanderer]

Minions, definitely minions. Go ahead and reskin Baphomet. Have fun--especially if this is a fight the PCs are looking for.

Baphomet is cr 23, no? You think a lvl 13 party can beat him?

For backup, maybe a Minotaur shaman/mage with counterspell and 2 more Minotaur thugs?

 

[prabe]

Baphomet is cr 23, no? You think a lvl 13 party can beat him?

For backup, maybe a Minotaur shaman/mage with counterspell and 2 more Minotaur thugs?

I had a party of six 13th level characters fight a death knight that did quasi-mythic stuff and turned into a deathwalker when they killed it. And it had friends.

Four-on-one, the action economy might not be quite so much on your PCs' side (and the PCs who fought the death knight punch a bit above their weight class--and had took an entire session to prep for the fight), but I'd feel reasonably confident they could handle Baphomet on his own.

 

[Quickleaf]

Nice, sounds like fun! We did one of these at the end of our Tomb of Annihilation game – the druid player took the reins for a 17th level one-shot using everyone's characters against his uber-grung druid. He definitely created a phased boss battle that started on the ground and then went into the air as the druid rode a roc through a storm.

Baphomet (MToF version) vs. your fresh 13th level party should be a good baseline.

A couple considerations:

• Average 13th level Hit Points are ~81 or so. On his turn Baphomet dishes out ~83 damage on average, so enough to down the average fresh PC, but not enough to kill them outright. That's about right for a serious boss encounter. Either Baphomet can threaten every member of the party each round, or he can mow down one of them, so that without healing / good strategy / luck, the fight would last ~4 rounds.
• Whereas your party is able to dish out maybe ~130 damage per round if not more, so they should be able to take Baphomet down in ~3 rounds barring one of them getting taken out of the fight.
• Besides Legendary Resistances (I often find those an unsatisfactory mechanic but YMMV), Baphomet has no way to shake off stun-locking. That's why I like "condition mitigating" traits – I'll post a sample of one of mine called Enduring below.
• If the paladin/sorcerer PC has Aura of Courage that will be a big help to nix the demon's Frightful Presence.
• You can use (or not use) Baphomet's Reckless Attack as a way to make the fight a little harder or easier on the fly, as this could grant the rogue PC advantage/sneak attack bonus damage with no effort required on their part.
• The archer fighter PC might be able to perch or maneuver out of Baphomet's range and snipe away, unless Baphomet burns its teleport to reach them, because Baphomet has no ranged attacks. That might be something to consider in your design of the map and area where the fight happens & how to use wall of stone to create cover for Baphomet.
• Finally the maze spell is one that requires special handling when deployed against PCs, in my humble view. When I had Acererak use it against a PC, I gave the player a little extradimensional space to explore and learn a couple facts & a weakness about Acererak within before finding his way back to the Material Plane.
• My instinct would be to use some kind of distance/reality-warping maze that allows Baphomet to manipulate the distance PCs are from him, essentially pushing the melee types further away, and pulling the archer closer in. Or things like there's suddenly a pillar granting Baphomet half-cover that just sprouted up out of nowhere. Kind of an extension of one of its lair actions.

Enduring. The elite gains these benefits:

• If the elite would be immobilized or restrained, the elite instead has its speed reduced by half and must repeat the saving throw at the start of its next turn; if it succeeds its speed remains half for as long as the spell or effect dictates it would be immobilized/restrained, whereas if it fails it becomes immobilized or restrained as normal.
• If the elite would be stunned or dominated, the elite instead grants advantage to all attacks made against it and suffers vulnerability against the next attack to hit it before the start of its next turn, and the elite must repeat the saving throw at the start of its next turn; if it succeeds it continues to grant advantage for as long as the spell or effect dictates it would be stunned or dominated, whereas if it fails it becomes stunned or dominated as normal.

 

[TaranTheWanderer]

Nice, sounds like fun! We did one of these at the end of our Tomb of Annihilation game – the druid player took the reins for a 17th level one-shot using everyone's characters against his uber-grung druid. He definitely created a phased boss battle that started on the ground and then went into the air as the druid rode a roc through a storm.

Baphomet (MToF version) vs. your fresh 13th level party should be a good baseline.

A couple considerations:

• Average 13th level Hit Points are ~81 or so. On his turn Baphomet dishes out ~83 damage on average, so enough to down the average fresh PC, but not enough to kill them outright. That's about right for a serious boss encounter. Either Baphomet can threaten every member of the party each round, or he can mow down one of them, so that without healing / good strategy / luck, the fight would last ~4 rounds.
• Whereas your party is able to dish out maybe ~130 damage per round if not more, so they should be able to take Baphomet down in ~3 rounds barring one of them getting taken out of the fight.
• Besides Legendary Resistances (I often find those an unsatisfactory mechanic but YMMV), Baphomet has no way to shake off stun-locking. That's why I like "condition mitigating" traits – I'll post a sample of one of mine called Enduring below.
• If the paladin/sorcerer PC has Aura of Courage that will be a big help to nix the demon's Frightful Presence.
• You can use (or not use) Baphomet's Reckless Attack as a way to make the fight a little harder or easier on the fly, as this could grant the rogue PC advantage/sneak attack bonus damage with no effort required on their part.
• The archer fighter PC might be able to perch or maneuver out of Baphomet's range and snipe away, unless Baphomet burns its teleport to reach them, because Baphomet has no ranged attacks. That might be something to consider in your design of the map and area where the fight happens & how to use wall of stone to create cover for Baphomet.
• Finally the maze spell is one that requires special handling when deployed against PCs, in my humble view. When I had Acererak use it against a PC, I gave the player a little extradimensional space to explore and learn a couple facts & a weakness about Acererak within before finding his way back to the Material Plane.
• My instinct would be to use some kind of distance/reality-warping maze that allows Baphomet to manipulate the distance PCs are from him, essentially pushing the melee types further away, and pulling the archer closer in. Or things like there's suddenly a pillar granting Baphomet half-cover that just sprouted up out of nowhere. Kind of an extension of one of its lair actions.

Oh crap. I will edit this in the OP. There is no Arcane Archer. It’s a 13th level divination wizard. I got one of the PCs mixed up. Wizards add a whole other level to encounters.

 

[Blue]

As a finale of a campaign, one of the players is being transformed into a demon and will take on the party. It's supposed to be a fun 'what if'/alternate finish one-shot adventure but I need help balancing things.

The player is a minotaur barbarian with Polearm Master, Sentinel and Great Weapon Fighting.

What CR creature should I be looking at? The party is 13th.
A Paladin/sorcerer with incredibly high AC
A rogue/warlock/bard. Essentially some smiting and misty stepping with a touch of sneak attack
A tabaxi monk who specializes in stun locking and incredible movement (including mobility)
An straight divination wizard. Force wall, magic jar, teleport, telekinesis and some battlefield control spells.

We are thinking of just reskinning a demon Lord. There is a minotaur Demon Lord but he's CR 25 so I wonder if that might be too much.
I thought of reskinning a pit fiend. Replacing it's flight with a trample/shove ability, and reskinning some of its attacks and giving him some interesting legendary actions.

There will be a couple of encounters to wear down resources a bit, but not much. Also wondering if we should add some fodder to soak PC attacks since 1 vs 4 tends to be a slaughter.

Thoughts/ideas/comments?

At level 8 we've taken on CR 21 as the first encounter of the day. It was VERY SCARY, and we had people down and up, but no deaths.

PCs have some awesome capabilities when they know it's petal to the metal. Make sure to have legendary/lair actions, and legendary saves to help balance the action economy. Though a monk is just the one to burn though those saves.

 

[TaranTheWanderer]

At level 8 we've taken on CR 21 as the first encounter of the day. It was VERY SCARY, and we had people down and up, but no deaths.

PCs have some awesome capabilities when they know it's petal to the metal. Make sure to have legendary/lair actions, and legendary saves to help balance the action economy. Though a monk is just the one to burn though those saves.

The monk tends to ruin most combats. But I'm wondering if giving the boss sentinel and polearm master to AoO and stop crazy movement and prevent monk from moving too easily might be too powerful on top of everything. I'm not sure what powers to replace for that.

 

[prabe]

Proficiency in CON saves, and high CON. Then maybe a feature that gives it advantage on CON saves--maybe in circumstances that are straightforward for it to finagle, but not guaranteed.

Monks do tend to do bad things to boss fights. I'm tempted to houserule monks to only be able to use stunning fist once per target per round, but I would not institute that houserule right before a boss fight.