Cetus the Shore Stalker

Flash
{u}, Sacrifice an Island: Cetus the Shore Stalker
can't be blocked this turn.
{b}, Sacrifice a Swamp: You gain 1 life and draw a
card.
{u}{b}: Exile five target cards from an opponent's graveyard. Return Cetus from your graveyard to
the battlefield. Activate only as a sorcery.