Shanaya, Duchess of Underworld

When Shanaya, Duchess of Underworld enters the battlefield Surveil 2. (Look at the
top 2 cards of your library, you may put any number of them into your graveyard and the rest
at the top of your library in any order)
{x}{b}{t}: Return target creature with converted mana cost X or less from your graveyard to the battlefield.