Arm Unit

The Arm Unit is a defensive weapon of the Rebuild of Evangelion continuity, debuting in Evangelion: 3.0+1.0 Thrice Upon A Time as the guard force around NERV HQ and the crater holding Evangelion 13. Like the Mark series, each one is a specialized machine rather than a general-purpose Evangelion of the kind WILLE operates.

The film never speaks the weapon's name aloud; the label comes from a Making Of video released by studio khara. A 2011 Ikuto Yamashita concept drawing shows Arm Units stowed on Evangelion 13's shoulder pylons, and their similarities to the RS Hoppers of the previous film suggest the design may have started life as an early Hopper concept before being recycled.

Each unit consists of two arms and two shoulder pylons joined around a central sphere, with no legs at all; despite that, the drones display baffling agility in combat. The pylons carry SHV Progressive Knives, their primary armament, and the units fight chiefly with these blades.

Their second tactic is uglier: grappling a target and self-detonating, producing explosions strong enough to cripple an Evangelion. No plug entry point or external controller is ever shown, so the reasonable conclusion is that the machines run autonomously. Fans have noted the irony that the same film introduces the armless Evangelion Mark.44B alongside a NERV weapon built almost entirely out of arms, plus a resemblance to the Dwarf Gekko of the Metal Gear franchise.

NERV fields the Arm Units in numbers against New Unit-02α and Unit-08γ as the WILLE Evas descend toward Evangelion 13. The swarm opens with a strike at Unit-02's head; the Eva evades but cannot pin down the nimble drones, while Unit-08γ manages to destroy one in a burst of yellow and pink light. To break through, New Unit-02α jettisons its booster and detonates it among the swarm, clearing a path deeper into the crater.

Unit-08γ fares worse. Fighting on with a beam whip aimed at the drones' cores, it loses its left arm when one unit latches on and self-destructs, and the final three drones grab hold and explode together, leaving the Eva armless and partly inoperable. In the end the swarm accomplishes its real mission: cornering Asuka into turning Angel, the trigger for the next stage of Additional Impact.