On a CR basis Yeenoghu is CR 24 the same as an ancient gold dragon so in theory that should be a fair fight but a lot depends on the envoronment and tactics.
Yeenoghu only has melee attacks and a 30ft fear spell so of the dragon is able to stay more than 30ft in the air Yeenoghu can do nothing.
The dragon however has nothing to prevent Yeenoghu from casting teleport so in most envoronments he would be able to escape. Similarly if there is space to fly if things go badly for the dragon it would also normally be able to escape.
Unless you're looking at a greatwyrm, the dragon probably can't meaningfully damage Yeenoghu -- dragon claw/teeth/tail/wings are nonmagical (so Yeenoghu is immune), and Yeenoghu is also resistant to fire/cold/lightning, immune to poison, so most breath weapons (exception: copper) also won't do a lot. If the fight occurs outdoors we wind up with the dragon tickling Yeenoghu with breath weapon when it comes off recharge, and Yeenoghu retaliating with spiritual weapon for also negligible damage. If the fight occurs in enclosed quarters Yeenoghu wins pretty handily.
Defeat is the key word here, because if they fight on the prime material plane, Yeenoghu wouldn't be killed by a dragon since it's not on it's homeplane.
One way or another as DM i'd consider what's better for my campaign.
In our campaign, Yeenoghu is trying to make his way to the material plane. So, I am having the party find a way to defeat him or at the very least, send him back to where he came from. My setting is in Exandria (Critical Role Wildemount) and the party has found some of the vestiges of divergence. However, I think they might need some more help.
Use the innate spellcasting optional rules for the dragon and give it banishment. That's a charisma save, which is Yeenoghu's weakest stat, and stands a chance of getting rid of him without a protracted fight. He has legendary resistance, but the dragon could wear him down by making him burn it on other saves. It's not a guarantee, but it's a pretty good shot.
Stat wise? yes there are powerful dragons like ancient ones and greatwyrms have better stats than yeenoghu.
Story wise? depends on what dragons are in the setting. If they are rare legendary beasts then yes, if they are common but powerful animals then no.
As for an encounter for level 8 players. I don't think a dragon stat block is the right way to go because they are a high damaging monster likely to steal the spot light. Either use a large number of strong enemies that the dragon can soften up with it's breath for the players or use a stat block that is a buffer. Given Yeenoghu's abilities and character I think the best option is to make a high level twilight domain cleric who can make a buffed area of relative safety that yeenoghu can then use his disabling abilities and moving abilities to harass players out of. It may also be a good idea to use spells like crusaders mantle or abilities like
Legendary action:
Command Allies. Aurelia chooses up to three creatures she can see within 30 feet of her. If a chosen creature can see or hear Aurelia, it can immediately use its reaction to make one weapon attack, with advantage on the attack roll.
Im just curious to know your thoughts.
Sure why not.
On a CR basis Yeenoghu is CR 24 the same as an ancient gold dragon so in theory that should be a fair fight but a lot depends on the envoronment and tactics.
Yeenoghu only has melee attacks and a 30ft fear spell so of the dragon is able to stay more than 30ft in the air Yeenoghu can do nothing.
The dragon however has nothing to prevent Yeenoghu from casting teleport so in most envoronments he would be able to escape. Similarly if there is space to fly if things go badly for the dragon it would also normally be able to escape.
Unless you're looking at a greatwyrm, the dragon probably can't meaningfully damage Yeenoghu -- dragon claw/teeth/tail/wings are nonmagical (so Yeenoghu is immune), and Yeenoghu is also resistant to fire/cold/lightning, immune to poison, so most breath weapons (exception: copper) also won't do a lot. If the fight occurs outdoors we wind up with the dragon tickling Yeenoghu with breath weapon when it comes off recharge, and Yeenoghu retaliating with spiritual weapon for also negligible damage. If the fight occurs in enclosed quarters Yeenoghu wins pretty handily.
I think the gemstone dragons have the greatest chance of success. But they are not necessarily good.
"Sooner or later, your Players are going to smash your railroad into a sandbox."
-Vedexent
"real life is a super high CR."
-OboeLauren
"............anybody got any potatoes? We could drop a potato in each hole an' see which ones get viciously mauled by horrible monsters?"
-Ilyara Thundertale
Or teleport onto the back of the dragon and prepare to shred it with his millions of melee attacks.
Defeat is the key word here, because if they fight on the prime material plane, Yeenoghu wouldn't be killed by a dragon since it's not on it's homeplane.
One way or another as DM i'd consider what's better for my campaign.
In our campaign, Yeenoghu is trying to make his way to the material plane. So, I am having the party find a way to defeat him or at the very least, send him back to where he came from. My setting is in Exandria (Critical Role Wildemount) and the party has found some of the vestiges of divergence. However, I think they might need some more help.
Yeah how easy or heard it will be for the party to defeat Yeenoghu with help of a dragon will depend of it's age category and their level?
They are currently at level 8.
Use the innate spellcasting optional rules for the dragon and give it banishment. That's a charisma save, which is Yeenoghu's weakest stat, and stands a chance of getting rid of him without a protracted fight. He has legendary resistance, but the dragon could wear him down by making him burn it on other saves. It's not a guarantee, but it's a pretty good shot.
Medium humanoid (human), lawful neutral
They;re very low level to fight Yeenoghu CR 24 and would need an Adult or Ancient Dragon to survive, especially if the demon lord is in his lair.
Stat wise? yes there are powerful dragons like ancient ones and greatwyrms have better stats than yeenoghu.
Story wise? depends on what dragons are in the setting. If they are rare legendary beasts then yes, if they are common but powerful animals then no.
As for an encounter for level 8 players. I don't think a dragon stat block is the right way to go because they are a high damaging monster likely to steal the spot light. Either use a large number of strong enemies that the dragon can soften up with it's breath for the players or use a stat block that is a buffer. Given Yeenoghu's abilities and character I think the best option is to make a high level twilight domain cleric who can make a buffed area of relative safety that yeenoghu can then use his disabling abilities and moving abilities to harass players out of. It may also be a good idea to use spells like crusaders mantle or abilities like
from Aurelia
This is awesome. Thanks guys