Arm-mounted Drill

The arm-mounted drill is an unconventional piece of weaponry used by shinobi from Yumegakure 's Tenrō clan .

The weapon itself is a large drill worn on the underarm, usually in a dual fashion. The drill can be used as a thrusting weapon, adding extra damage as it spins, but also allows for swift underground movement, enabling the user to ambush opponents from beneath, similar to a number of ninjutsu .