Boone, Undesirable's Guide

Into the breakout room - Whenever a creature blocks or becomes blocked by Boone, exile that creature until it's owner's next upkeep. Then, flip a coin. If you win the flip, that creature enters with an upstanding citizen counter. It can't attack you or planeswalkers you control. Otherwise, it enters with an undesirable counter and gains "at the beginning of your end step, you may pay{1}. If you don't, sacrifice this creature."

{2}Target creature blocks Boone this turn if able.