Loki, Insidious Trickster

Loki can't attack or block unless your favor
towards blue and black is at least five.
Whenever Loki attacks, you may have it become a
copy of target creature, except its name is Loki,
Insidious Trickster, and the creature copy has all
abilities this card has.
{u}, Discard a card: Put Loki from the battlefield
on top of its owner's library.