Brirdor, Titan of Sky's Frost

When Brirdor enters the battlefield, sacrifice it
unless it escaped.
Whenever Brirdor enters the battlefield or
attacks target creature your opponent controls
and all creature with flying that opponent
controls can't block this turn.
Escape—{w}{w}{u}{u} Exile five other cards from
your graveyard. (You may cast this card from your
graveyard for its escape cost.)