Jareth, True Goblin King

{u/b}{u/b}{2}{t}: Steal target creature. It becomes
a 3/3 goblin in addition to its other types.
Whenever a creature you control dies, if it
isn't a goblin create a 1/1 Goblin Creature token.
Sacrifice a goblin to create {x} colorless mana where {x} is that creatures toughness.