Portal Sentinel

When Portal Sentinel enters the battlefield, if it entered from exile, you may choose a card in exile and return it to its owner's hand. Otherwise, shuffle target exiled card into its owner's library.
{1}{g}{g}, {t}: Exile Portal Sentinel. Return it to the battlefield under its owner's control at the start of that player's next turn.
Nothing is lost to them, even in the Blind Eternities.