Darkbeast Paarl

Flash, Persist
Prowl{6}{u/b}:(You may cast this for its prowl cost if
you dealt combat damage to a player this turn with a
Beast or Hunter.)
When Darkbeast Paarl enters the
battlefield, if its prowl cost was paid, it deals
{x} damage to any target, where x is equal to the
number of creatures in your graveyard.