Out of the Abyss - Final Battle (Minor Spoilers)

[Princess]

Officially the end of Out of the Abyss is written for 5 level 15 characters, but presently a party of 5 11th level characters are nearing the end and it doesn't look like they'd get past 13 before the big fight without changing things around or adding a bunch of random encounters or quest xp. Question - have any DMs who've run OotA or a similar scenario had enough experience with this to gauge the odds of a total party wipe if 5 characters in the level 11 to 13 range try and face Demogorgon?

[ATHATH]

You could bring in some Angels or Devils (remember that the Blood War is a thing) to help them out. Have them approach the PCs before the battle/at the beginning of the session/last session so it doesn't seem like a deus ex machina, and maybe let the players control them. Another alternative to make it seem less cheap is to make the helpers Yugoloth mercenaries, which will demand payment.

Alternatively, if all else fails, just bump them up 2 levels at the beginning of the session. Say that the forces of Good (or LE) are empowering them or something).

[silvertree]

SPOILERS AHEAD, OBVS

I think our group (6 players) were around level 9 when we finished OoTA.

Our DM had us each play as one of the demon princes in the final showdown, with 2 players controlling Demogorgon (one for each head). The idea was that they all hated each other, and all blamed each other for being pulled to this central location. The intent of the DM was that there would be one surviving demon prince, and that one would be significantly reduced in power after the battle royale.

And it went pretty much according to plan. Each of the princes expended their spells/resistances/wand usages. But the player controlling Graz'zt decided he would try to avoid the fight, and spent the entire encounter running/teleporting away. Our DM decided then that the object used to summon all of the princes had a tether effect with it, and if a prince got too far away from it they'd be pulled back to the center of the area.

Even that, however, wasn't enough, since Graz'zt could still run and teleport, thereby avoiding battle with the other remaining prince. So the DM added to the tether effect a damage-increasing AOE that accompanied the tether pull. The end result was that the final 2 demon princes died in this AOE effect.

The players, as their normal characters, spent the first 30 minutes or so of the session putting the finishing touches on our strategy for dealing with the final prince, whoever it would be. The rest of the session was this battle between the princes. I had a great time, and feel like most of the players did as well. And I feel like our characters could have taken the weakened Demogorgon (he being the other last prince) had the Graz'zt scenario not taken place. The finale was a little anti-climactic, since none of our characters got to land the killing blow. But the fight between the princes was sufficiently intense.

I will say, however, if Orcus would have been the surviving prince, I don't know if the characters would have won the day.