When you play Blissey from your hand, you may flip a coin. If heads, remove 8 damage counters from Blissey. If tails, remove 4 damage counters from Blissey. Either way, if Blissey has fewer damage counters than that, remove all of them.
Body Slam のしかかり
Flip a coin. If heads, the Defending Pokémon is now Paralyzed.