Biv Glizzet, Son of Niv Mizzet

Flying, Haste
Whenever Biv Glizzet enters the battlefield or attacks, put a +1/+1 counter on it.
{u/r}{u/r}, Remove X +1/+1 counters from
Biv Glizzet: Gain control of target instant or
sorcery with mana value X or less. You may
choose new targets for that spell. Then copy
it. You may choose new targets for the copy.