I Stole Your Fates Long Ago.

When you set this scheme in motion, for the
rest of the game, each card you control may
treat any card in exile as though it had been
exiled by that card.
At the start of your precombat main phase, each
opponent mills 5 cards and you may play a card
from exile. You may spend mana as though it
were mana of any color to cast it.
When a total of three draws and/or looks from
one library is reached, abandon this scheme.
(Each card in each "look" counts. toward this.)