Kaylus, soul exchanger

{g/w}{t}:put a soul counter on target creature
pay 2 life, {b}{ut}:sacrifice a creature
Whenever a creature with a soulcounter is put on
a graveyard, move that counter to another target
creature on a graveyard, act as that creature is on
the battlefield. Whenever a creature with a soul
counter that is on a graveyard is destroyed exile it
and move its soul counter to target creature on the
battlefield.