The Iron Throne

At the beginning of your upkeep, choose one:
•Until end of turn, you may sacrifice three
non-token creatures, if you do, you become the
monarch.
•Until end of turn, you may sacrifice a non-token legendary human, if you do, exile target creature.
•At the beginning of your post-combat main phase,
target opponent becomes the monarch. Add {4} to
your mana pool.