Hi everybody - for my ongoing campaign, I have a huge (8, plus or minus some guests that come in and out) party of lvl 14 PCs. They're taking sort of a side mission in their upcoming session, and I want it to have the same vibes as that of the movie Alien vs Predator. 

That is to say, they stumble into some ruins that are actually ancient hunting grounds, where one advanced hunting race (Predators in the movies, most likely Braxat in my game) hunts down an evolutionary specialized killing machine type of monster. 

I've got all of it planned out, but can't quite figure out which beastie I want to have the Braxat hunting. Does anyone have good ideas (besides like, dragons) for high CR creatures that would be a good fit? They can be either a deadly encounter that the players need to run from, or a fight they might win. Either way works for me, so long as the maintain that sort of killing machine vibe that the Xenomorphs from Alien have. 

Thanks!

I mean, the Steel Predator (I think it's called) is literally an Alien:

(pic lifted from a google search)

I think it's around CR17? or thereabouts? It's in Mordenkainend Monsters of the Multiverse.

Sounds like a cool game, I am curious as to how you will get the vibe - alien movies have always been about whittling the survivors down. 

I have considered a "zombie mode" kind of game where as soon as a player dies, you start narrating to them - openly, in front of the other players - them waking up, hungry, and smelling something on the air. Give them a stat-block and not only are they in the game still, but the tension just got so much higher. "You find a dead alien on the ground..." (other players) "oh god they're right behind us! Run!".

Good luck, and let us know how it goes!

What if you took something like an Iron Golem and had it be like a modified design? Someone created the ultimate killing machine, and lost control and now they are running wild. You could even model it off the Xenomorph, its just artificial?

Both of those are good choices. Despite my (apparently terrible) choice of words, I actually want the *alien* force to be a living creature, not a construct. If need be I'll just reskin Steel Defenders and/or Iron Golems into what I want, but I was hoping to see if there were any flesh-and-bone beasties that I could use RAW. 

You might find this useful, I remembered reading about someone doing this a while back https://www.pirategonzalezgames.com/piratesblog/2019/2/20/alien-vs-predator

I think I've settled on either Slaadi or Behir. Both give an element of the fun dangers I'm looking to capture, and in the moment I'll just have to decide on which one to use. Thanks for the suggestions everyone!

I recommend the Slaadi, they have a similar life-cycle to Xenomorphs

I turned the dungeon into a Braxat hunting ground where they breed Behir to hunt down as a sort of 'Rite of Passage'. It was very fun, the players had a blast and actually managed to do just about everything I was hoping they would (which, as a DM, we know doesn't happen often). It gave most of the AvP vibes I was looking for while still maintaining the spirit of the one-shot I was going for. Overall a great session. 

Sounds like it was fun, glad it worked out.