ESU-S4xA-017 Diamondback

The Diamondback is an overall improvement of the Majestic, and the perceived sister unit of the Zephyr. It originally had no weapons in its use (being a prototype unit), but was given close-quarters equipment to effectively make use of the suit’s unmatched speed. It was stolen by the Mercury Legion during the Fall of the NDRC, eventually becoming the personal machine of the Legion’s leader—Jack Kendall.

Armaments
- Stingblades: The primary weapons of the Diamondback. They are made out of a strong metal capable of breaking through Garrisai armor, similar to the Anti-Armor Sabers of the Arodnight. Each of the two blades are mounted on each forearm under the Breaker Shields, and flip out from under the shields when deployed. They are unable to be handheld

- Breaker Shields: Each forearm has a medium-sized shield used for blocking and guarding the Stingblades when not in use. Both shields have a spiked knuckle mounted on the front for punching attacks (and when the blades are stored away or destroyed). If need be, the shields and swords can be purged, breaking off of the forearm. (Custom version of the Nanolaminate Compact Shield)

- 40mm Tactical Assault Rifles: This pair of 40mm ASUs have been compacted down to resemble Submachine Guns. Featuring a shorter barrel, drum magazine, and folding stock, these weapons serve as the primary ranged weapon of the Diamondback. However, Jack will commonly prioritize the 80mm Autocannons for ranged attacks, due to his dislike of handheld weapons. When not in use, they are stored on the rear skirt armors.

- 80mm Autocannons: These shoulder-mounted Guns can provide suppressive fire if an enemy is too far away for the swords to reach. They serve as an alternative to the Swarmfire Missile Silos. At mid-range, they sport a notable stopping power when put up against approaching machines. Their lack of accuracy further encourages their use when up close and personal with the enemy.

- Swarmfire Missile Silo: Each shoulder armor has a built-in silo that can store up to 25 missiles each. The missiles can be guided to lock on to a target via the Custom ATS. When activated, each of the door flaps in the shoulder armors flip outwards, revealing the silos inside.

- Actuator Knuckle: A large forearm gauntlet that has a much stronger break power than the Breaker Shields themselves. While it can strike its opponent with the gauntlet, it is also equipped with a built in needle that can shoot out from inside the gauntlet, impaling anything in its way. It was designed as a countermeasure to heavily armored chest-plates of Garrisai, so that the pilot could still be attacked. This weapon can be perceived to operate in a similar manner to the Factory Buster.

Special Equipment and Features
- Custom ATS w. METACOM System: This special version of the ATS has been programmed to run effectively with HMTs. It can target moving enemies even when at high speed, and fire weapons automatically. It was designed to be paired with a METACOM System, and would provide a level of performance akin to some BURST RAID Units, without the need of an AI construct. Eventually, this ATS would be paired with an actual NU METACOM System when the Diamondback was upgraded into the Onyx.

- External Fuel Canisters: If needed, the Diamondback can be equipped with an external pair of fuel canisters for long distance travel or extended operations.

History
After the Rocket II was captured by the Jack Kendall himself, it was upgraded under his personal preferences. He would use it regularly while Decholon was under Armeli Control, as well as for countering the UNI and LCR forces. After attempting to save Miia from the clutches of the LCR, Jack had his Diamondback upgraded into the Onyx.

- The Diamondback and Majestic had drastically different versions of the HMT II System, with the former being more advanced than the latter. This was because it remove the need of a Gyrotumbler unit. When the machine was stolen and its data archives deleted, the LCR had to redevelop an entirely new HMT II System, once again using the Majestic as the test subject, as it had the older version of the system itself.

Trivia
- The Diamondback has a similar design to the Grimgerde of IBO.

- The Actuator Knuckle has a similar extension mechanism to Barbatos’ Mace, and the RX-0 Banshee’s Armed Armor “Claw.”

- The Diamondback gets its name "canonically" from its coincidentally shaped HMT II Diamond Thrusters. They provide multidirectional movement on all four sides in a single unit.

- Its real-life name origin came from the Diamondback Revolver of TF2.