John, Mystic Maestro

{1}: Exile an instant or sorcery from a graveyard
face up. Then change the attack target of target attacking creature to another valid target ( it
cannot attack it's controller ).
{t}: Target an instant or sorcery on the stack and
select a face up card exiled by John, Mystic
Maestro that has the same mana value as the
target. The target becomes a copy of the selected
card until it leaves the stack. Flip the selected
card face down.