Bo, Maddening Magus

+1: Bo, Maddening Magus deals 2 damage to target creature. At the beginning of the next upkeep, that creature deals 3 damage to itself.
-3: Gain control of up to one target creature an opponent controls and give it haste until end of turn, Untap that creature.
-6: Bo, Maddening Magus deals 6 damage to up to seven target creatures, for each one that dies this way, that creature's controller takes 6 damage