"Shits and giggles" is not a valid reason to use a psychic power and risk The Perils of the Warp in Dark Heresy. We're supposed to be looking for signs of daemonic taint, and not by causing the 6000 people that occupy the block in the hive city we're in to become possessed by Khorne and become extremely hostile, just because you thought it would be funny to flood an informant's kitchen with rats and roaches while they were trying to find something to eat.
Actually, it is a valid reason, since most of the fun in Dark Heresy comes from things going horribly, horribly wrong.
ace_of_something said:
Our groups are only allowed one montey python and the holy grail quote per gaming session.
Otherwise it gets out of hand.
In my group it's busting out rhymes from old school hip hop, and it is totally forbidden. If someone can't control themselves and lets "he can't satisfy you with his little worm, I'll bust you up with super sperm" escape their lips, within a blink of an eye we are no longer interested in the game, and are more interested in shouting the entirety of "No Sleep Til Brooklyn" in unison.