Necron Deathmark

Deathtouch
Overwatch— {p/g}{p/g}{p/g}: Until your next turn, if a
creature attacks you, Necron Deathmark deals 3
damage to target creature attacking you, tap
Necron Deathmark. Activate only as a sorcery.
{p/g}{p/g}{p/g}{p/g}{p/g}{p/g},{t}: Necron Deathmark deals 3
damage to target creature. Activate only as a
sorcery. If you paid life to activate its abilities,
discard a card.