Cyrelle, Secret Keeper

Indestructible
As long as your devotion to blue or black is
less than 4, Cyrelle isn't a creature.
{u/b}: Target creature is unlockable until the end
of the turn
Whenever a creature you control deals combat
damage to a player, that player exiles a card from
the top of their library, you may cast cards exiled
this way and spend many of any color to
cast them.