How I handle it as a DM
*the combat rages*
*player rolls a nat 1*
*the fight stops*
*the boss and all his minions start laughing*
*the player takes vicious mockery damage each turn that a minion is laughing*
Whilst they are laughing they are considered prone and can't take an action. They only stop if they take damage, a spell effect tagerts them, an ability targets them.
This will simulate the character messing up. A croud laughs at him, and then he flies into a blind rage attacking everyone who laughed at him. All while suffering emotional damage.
