The Chosen One

Haste, resist black ( Prevent all damage from a
black source dealt to this creature.)
{x}, {t}:Search your library for a creature card with converted mana cost X or less, reveal it, and exile
it with a chosen counter on it. Then shuffle your library. Chosen becomes a copy of that card, it's legendary in addition to it's other types, and it
gains haste, resist black, this ability and gets
+4/+4. This effect will remain for the duration
of the game or another card replaces it.