Gredi, Arcane Tyrant

Adamant — If at least three black mana were spent to cast this spell, each opponent discards a card from their hand.
Adamant — If at least three blue mana were spent to cast this spell, draw three cards.
Whenever Gredi, Arcane Tyrant dies, each opponent loses life equal to your devotion to black, then each player mills cards equal to your devotion to blue.