Master Xehanort, Dark Seeker

When Master Xehanort, Dark Seeker enters the battlefield, surveil 1. (Look at the top card of
your library. You may put it into your graveyard.)
{x}: Master Xehanort, Dark Seeker becomes a
copy of target creature card in your graveyard
with converted mana cost X, except its name is
Master Xehanort, Dark Seeker, it's legendary in addition to its other types, and it has this ability.