Ezreal, Mystic Challenger

Haste
Whenever Ezreal attacks, you become the Monarch.

At the beginning of your end step, if you are the Monarch, you may cast a nonland card from your graveyard for free. Exile it at the beginning of the next end step.

When Ezreal enters the battlefield or attacks, you may pay {x}{u}{r}. If you do, Ezreal deals X damage to any target. If that damage causes a creature to die, create a 1/1 red and blue Elemental creature token with flying.