Ixhel, Scion of Atraxa

Flying, vigilance, toxic 2
Corrupted — At the beginning of your
end step, each opponent who has three or more poison counters exiles the top card of their library face down. You may look at and play
those cards for as long as they remain exiled,
and you may spend mana as though it were
mana of any color to cast those spells.