Chos, Thought Reaper

Whenever a card is discarded or milled, exile it.
{p/u}{p/b}{p/r}: Each player discards a card, mills a card,
and draws a card. Exile Chos, Thought Reaper.
Activate this ability only any time you could cast
a sorcery.
As long as Chos is in exile, you may play cards
from exile. At the beginning of your upkeep,
return Chos from exile to its owner's hand.