Demiurge, 7th Guardian

Exploit
{1}{u}{b} : Monstrosity 2.
When Demiurge becomes monstrous, it gains
Flying and "{u}{u} : tap target creature"
When Demiurge exploits a creature, look at the
top four cards of your library. Put one of them
into your hand and the rest into your graveyard.
If you wish, I will immediately bring the armies of Nazarick and take this jewel box.