Specter of Forgotten Lore

(If {u/b} was payed with {u}, this creature is blue and
black.)
When Specter of Forgotten Lore enters the
battlefield, If it's blue, look at the top X cards of
your library and put a card from among them
into your hand and the rest into your graveyard
or shuffle them into your library. X equals your
devotion to black.
As long as Specter of Forgotten Lore isn't blue, it
gets+2/+0 and gains flying and prowess.