Creature Seed: Murder Cheese.

Murder Cheese – Google Docs

Murder Cheese

You can eat it.  But you should not eat it, because if you ever see any, it was probably sent by an enemy that is trying to kill you.  Consuming any of the stuff will merely make the actual assassination itself a bit of a formality.

Murder Cheese resembles a two pound block of what looks like a certain (and famous) type of easily-melted, remarkably homogenized cheese-like product. Which is what it is, with the addition of a bound minor demon that has been assigned the task of finding, then murdering, its designated target. The demon will usually have an instinctive idea where its quarry is, and has enough rudimentary psychic-occult ability to subtly nudge people to take the Murder Cheese in the general direction of where it wants to go.  It has rather more power over its form; assume that it can do anything, say, a liquid-metal time-traveling assassin can do, only it’s still made out of cheese and can’t change color.  The demon is smart enough to be self-aware, but it is not particularly insightful.

Murder Cheese has three great advantages to it: the base material keeps indefinitely, the imp possessing it can’t be particularly reasoned with, and suffocation (the Murder Cheese’s usual assassination method) is both hard to trace, and easy to disguise as something else.  Biggest disadvantage?  Murder Cheese has no interest in being quiet and peaceful after it has murdered its target. Typically, the spell that creates this stuff is designed to rapidly shut down once the murder is done, but sometimes safeguards fail.  When that happens, the Murder Cheese will just kill flat-out people whenever it thinks that it can get away with it.

Fighting a Murder Cheese: fire, acid, or cold all works pretty well.  So does getting it into an airtight container.  Punching or stabbing it?  Not so much.