Ninja's Kunai

Equipment that spends itself. Most gear sticks around to keep granting its bonus turn after turn; this one loads a single detonation onto a creature and then vanishes when the trigger is pulled, converting a body's tap into three damage aimed anywhere. That structure does two useful things at once. It hands an evasive attacker a way to close out the last few points without ever entering combat, and it turns any creature (even one with no offensive stats at all) into a removal outlet, so long as you can pay the mana and afford to sacrifice the artifact. The sorcery-speed equip is the price of admission: you commit the mana on your own turn, then choose the moment to fire, rather than ambushing at instant speed on someone else's. And because the granted ability sacrifices the Equipment as part of its cost, the tension is in the timing, not in protecting the wielder: if the creature dies before you pull the trigger, the Kunai stays on the battlefield, ready to be re-equipped to something else for another . Only firing it destroys it. The flavor of a thrown blade fits the mechanic exactly: one strike, one target, and the weapon is gone; leave it sheathed and you keep it.