Wow! I've fallen waaaay behind on this thread.
In order to try to catch up, let me break it apart and give you my initial thoughts:
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I've falled way behind on this thread too.
Let me know how all that meshes with what you've previously discussed.
I don't see anything I disagree with.
We've mostly agreed that the aruchai transform into the creatures they kill and somehow transfer to that creature's home plane. The creature they killed becomes an arucha. Beyond that is a little fuzzy.
I'm a little bit lost to be honest. Hopefully, I haven't missed anything.
IIRC there is an ability (clerical) to dismiss outsiders back to their own plane. It feels like this is a parallel thing with the arucha somehow "stealing" the home plane (as well as the form) of its victim.
Here is something we haven't thought about yet: how fast does an aruchai hop over to its new plane? Does it wait for the end of the combat (in which case it might never get to happen unless you have a TPK) or does it instantly vanish as soon as someone gets absorbed and exuded?
I knew you'd remember what examples there were! We've basically agreed on this mechanic (though haven't thought about a solvent) but mostly for the weapons. Big Mac, if you agree, I'd like to go with sticking to creatures as well (and auto-grapple on a pseudopod attack, I guess). I suggested upthread doing X hp per round of acid damage and that weapons explode (as an acid flask?) when they reach 0 hp.
I would go further that this. I would want to go with it sticking to
everything that touches it (not just creatures and weapons). And I want anything that isn't a valid target for engulfing to cause an explosion.
Well, I'd put paralysis with the pseudopod attack, but yeah. I also think that we should bump these to Medium size if we're using the standard Engulf, so they can Engulf Medium PCs. Should they be able to Engulf a creature they've grappled through their adhesive?
I'm onboard with medium size.
I thought adhesive was their only attack, so I'd go with them being able to engulf grappled creatures. I think there should be a short delay or additional attack roll (like the illithid extract brain) so that they don't get a 100 percent kill rate.
Right. Probably should have a separate stat block, though, since this will be beyond the normal advancement, I'd guess. You mention below Gargantuan for the size. However, 5 cubed is more than 100 already, so 100 aruchai merged together only gives something about 5 times bigger in each direction. So I could possibly see Huge for the smallest colonies, even if we go with Medium.
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Yes on immunity to cold. I'm not certain on DR 5, but I'll go along with you as I've got no idea of my own (apart from it needs good DR).
I'm fine with fire, but vulnerability to acid makes no sense to me, since their adhesive does acid damage. Any thoughts about that?
I think I mentioned this before. Does
alkaline exist as a concept in D&D? Things like
caustic soda are just as destructive as acid, but have a PH at the opposite end of the scale. So you
could have a creature that has a alkaline attack and has acid vulnerability.
But if this concept doesn't exist, or if you think the monster is too complex for a GM, we could ignore the acid.
Both the adhesive abilities look good. I think I'll need to read 'em both and decide which is better.
I'm OK with the stats too. Should these creatures "steal" the stats of their victim after they transform?
These adhesive abilities are about the same (which is nice), so I'm fine with copying from any of them. We just need to decide if there is a solvent and what it is.
If we retain the acid vulnerabilty (i.e. make them have an alkaline attack) then acid could be a solvent. Otherwise I'd say that crushing the little red parasites would obviously give you something that stops the glue sticking.
I'm going to post what I've got now and keep reading.