Hecate, God of the Arcane

As long as your devotion to white, blue, and
black is less than three, Hecate isn't a creature.
Indestructible, deathtouch.
Whenever you cast an enchantment spell, exile
the top of each players library. You may look at
those cards and you may spend mana as though
it were mana of any color fo cast that spell.