Boros Mastiff

Battalion — Whenever this creature and at least two other creatures attack, this creature gains lifelink until end of turn. (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

From Magic: The Gathering.

Open the interactive version on https://mythscribe.cloud/app/tcg/cards/cms6o6mnk3usvpb1hy6nhizyr.