Hyrules Invasion

Battle(As a Siege enters, choose an opponent to
protect it. You and others can attack it. When this is defeated, exile it, then cast it transformed)[4HP]
When this enters the battlefield, each opponent sacrifices a land or a creature they control with
the highest power. If you control a commander,
do both.
When this is dealt damage, the next creature you
cast this turn costs {x} less. X is equal to the
damage dealt.