Megumin, Crazy Explosion Girl

Whenever a creature dies that was dealt damage
by Megumin, Crazy Explosion Girl during that
turn, Megumin, Crazy Explosion Girl deals
1 damage to every opponent.
{8}{r}{t}: This ability costs {1} less to cast for
every creature on the battlefield you do not
control. Exert Megumin, Crazy Explosion Girl,
and deal 13 damage divided between any number
of target creatures.