Gorz, Darkness Emissary

Can only be cast at instant speed after you lose life.

When Gorz, Darkness Emissary enters the battlefield, activate the correct effect for the origin of the damage you took to summon him:

Combat damage - Create a 0/0 black Darkness Emissary creature token with +1/+1 counters equal to the amount of damage you took.

Effect damage - Target player takes damage equal to the amount of damage you took.