While being on a run, I have found some imp-like creatures that shouted a brief message saying they would not attack me. I tried hitting them, and occasionally killed one.
What purpose do these have? I received plenty of goods from killing them, so I don't really have an incentive not to kill non-hostile NPC's?
http://forums.spiralknights.com/node/368
It comes in almost the same fashion of the heart puppies (don't know if you found it yet, but it's a gun puppy that shots hearts to you...and have a chance to drop a rare iten, and now that i know this, i can't find it anymore). Also, innofensivee npcs that yet can be killed would not be so good, because, or they would have nothing to drop, or simply would function as a way to give some fast money and itens if one is lucky, with no dificulty. Also, attacking a hopeless monster/animal is cruel, and no fun at all...
I like, though, the idea that the monster isn't agressive at all, till you attack him, or do something like pressing a switch (not that the monster will spawm when you press, but the mosnter is already there before you press the switch, just ignoring you), more or less like the tortodrone.