I'm with Monolith on this...after all, there has to be some set of rules regarding the Thing...it can't just float into the center of a quasar and replicate the matter present...it's not perfect...so in my fantastically magic
alterverse, were these three creatures meet (somehow), this is how it would play out:
ALIEN - We start at Stage One of the Alien life cycle, Thing has to be something moving already - searching for the next creature to replicate, it won't just sit still in ambush somewhere, it wants to spread...so Thing replicated creature strolls into a cave with our favorite alien's egg, it triggers the facehugger and allows itself to act as a host (I know, I'm stretching, but the Thing played along and allowed itself to be tied and tested before it reacted violently), if anything, because it's like, "Hey! New creature to copy. Cool Beans!"...by now, facehugger has been doing it's thing and an embryo is on the way...FH comes off and a piece of Thing replicated creature comes off with it, starts doing it's thing, becomes a FH and scurries off, whatever...our Thing replicated creature gets up carrying a cute and cuddly lil' xeno embryo...embryo matures, Thing thing convulses and drops, alien born...Thing creature is not dead, so it gets back up and carries on doing Thing related things...chestburster matures, appearance is similar to whatever the Thing originally copied...extra bonus: auto-replicating exoskeleton, +Infinity stealth pts...alien gets up and continues doing xenomorph things...the end...
PREDATOR - Much simpler...predator mask picks up on whatever it is that the fat Doc with glasses (Blair?) saw through his old ass, early 80s era microscope (Predator tech pwns human tech, no contest here)...so our predator knows something is fishy in Chinatown with Thing replicated creature the minute is comes into view...it puffs it's chest out and plasma casts it...mask still picks up on molecular activity, plasma casts again - repeat...Thing thing is reduced to a pile of ash, or whatever...predator is mad he has no trophy, runs along all PMSing...the end...
Fuuuuuuuuuuuuuuuuuuuuuuuccck the Thing..!
DISCLAIMER: I love
The Thing, great creature, great story...but this is
Av
P, sellouts...go blow the Thing on it's own forum...