Burgen Glade

Burgen Glade enters the battlefield tapped.
As Burgen Glade enters the battlefield, you may
exile three target cards from your graveyard. If
you don't, exert Burgen Glade.
{t}: Add {b}{g}, {b}{c} or {g}{c}
{x}{c}, {t}: Exile X target cards from a graveyard.