The Raven Queen

When The Raven Queen is put into the
graveyard or exile from anywhere, put it back
into your library third from the top.
Flying, First strike, Deathtouch.
Whenever a permanent you control is put in the graveyard from the battlefield, surveil 3. You
may return a non-creature permanent from your graveyard to the battlefield with lesser mana
value than the triggering permanent.