Rayis, The Savior

Flying, Haste
When you cast Rayis, deal X damage to each
creature where X is equal to the mana spent
to cast Rayis.
At the beginning of your upkeep exile the top
card of your library. Until end of turn you may
cast that card for as long as it remains exiled.
When you do, that spell costs {1} less for each 1
life your opponents have lost this turn