Throwing Knife

Text:

Equipped creature gets +2/+0.
Whenever equipped creature attacks, you may sacrifice Throwing Knife. If you do, Throwing Knife deals 2 damage to any target.
Equip (: Attach to target creature you control. Equip only as a sorcery.)

Rulings:

• 6/22/2015 Throwing Knife’s triggered ability triggers before blockers are declared. If you use the ability and destroy the targeted creature with lethal damage, it won’t be on the battlefield to block.
• 6/22/2015 Throwing Knife is the source of the damage dealt because of its triggered ability. For example, you could sacrifice Throwing Knife to deal 2 damage to a creature with protection from red, even if Throwing Knife is equipped to a red creature.