Popi , Rakdos Trickster

Popi, Dimir Trickster cost {1} less to
cast for each time you dealt damage this turn.
Protection from instants.
{p/b}: You choose new targets for 1 damage dealt to target permanent.
If you dealt 5 damage to an opponent, you may pay {5}{r}{b}, if you do,
transform Popi, Dimir Trickster.