Luna, Titan of Humanity

When Luna enters the battlefield, sacrifice it
unless it escaped.
Vigilance, lifelink
Whenever Lin enters the battlefield or attacks,
each player may gain 3 life and draws a card.
Escape—{w/u}{w/u}{w/u}{w/u}{w/u}, Exile seven other cards
from your graveyard. (You may cast this card from
your graveyard for its escape cost.)