Interesting assortment of responses, hah. XD
@soignee, contact poisons are a good possibility too... makes me think of the poisoned dress in "Elizabeth"

Creature 1 wrote...
Sure he could have. For some reason that's more disturbing than poisoning their drink, too. These kinds of irrationalities are quite interesting.
For what it's worth, I don't think such a thing is possible.
Yeah, I'm trying to think about it logically and I don't see how the poison would still be concentrated enough... or whatnot..

But if it
sounds like he could have, in the game canon... *scratches head*
@ejoslin, hmm.. I'd need the exact quote (on a laptop at the moment), but the fact that he talks about poisons "harmless to him" but killing the warden "as we speak" kinda inferred to me that he could have poisoned the Warden while they were having their tent time. Through whatever method.