Sion The Juggernaut

0: Each time a creature leaves the battlefield this turn put a loyalty counter on Sion The Juggernaut
-X: Remove X loyalty Counters from Sion The Juggernaut, destroy target creature with mana value X or less
-15: Until the end of turn Sion The Juggernaut becomes a 20/20 undead berserker with haste, trample, indestructible and deathtouch.