Tainted Cultist

As an additional cost to cast this spell pay
({p/g}/{p/b})
Whenever Tainted Cultist enters the battlefield,
mill four cards.
Pay 2 life, exile a creature: Tainted Cultist base
power and toughness become a 4/3
Pay 5 life, sacrifice a land: Tainted Cultist
becomes a 5/3 demon with flying.