Mad Madam Mim

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