Grudge Wrath

Grudge Wrath costs {1} less to cast for each
creature you control that has died this turn. If
three or more creatures you control have died
this turn, you may cast it as though it had flash.
At the beginning of each end step, if a creature
you control has died this turn, Grudge Wrath
deals damage to any target equal to the number
of creatures you control that have died this turn.