Egads, more CC for fire? O_o
I'd change the wording a bit, it seems... a little awkward. "Target creature is put in stasis for one turn with a 50% chance to be infected" might work better (poison is for the player, infection is for creatures)
Also, I think the ability would fit death better... maybe change the cost to 2
?
I like the idea, though. I think it could open up synergies with time (combined with procrastination and scarabs), death (or rather, strengthen those synergies), gravity (again, helping get creatures into munching range and strengthening existing synergies), and life (combined with thorn carapace for lots of infection)