Hasn┤t any of the characters in your game done something so stupid,nonsense or simply outrageous?

I remember while DMing Return to the Tom of Horrors that after having explained thoroughly and lengthfully to the players how careful they had to be with the Necromancers near the tomb┤s entrance(There┤s a whole school of Necromancers here,okay? Remember:a whole school filled with mages with high level teachers. ) they went to an inn and the fighter bumped into a Necromancer at the inn┤s door.
The Necromancer said something like:
You moron!! Mind your step!!
Fighter: I chop his head off......

He actually did.