Very similar to Berserk Button
in which a character becomes angry to the point of resorting to violence. This trope is where a character becomes cruel and callous. Perhaps he lost the game and became a bit of a sore loser. Maybe he's been hanging with the wrong crowd as of late
. Perhaps someone should at least mellow him out before he takes his jerkassery to a whole new level.
May be the explaination why the character Took a Level in Jerkass
. If the character pressed the button on his own without the help of others, then it's Bitch In Sheep's Clothing