Golgari Keyrune

{T}: Add {B} or {G}. {B}{G}: This artifact becomes a 2/2 black and green Insect artifact creature with deathtouch until end of turn.

From Magic: The Gathering.

Open the interactive version on https://mythscribe.cloud/app/tcg/cards/cms6ogx73c4ivpb1hdz10olv2.