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Captain Wallace was an officer in the UNSC Navy during the early stages of the Human-Covenant War. In 2525, he was Captain of the UNSC Commonwealth, a Frigate. During his career, Wallace lost his left arm below the elbow, though he continued to perform his duties, commanding his warship against the UNSC's enemies, including the Covenant.
Battle of Chi Ceti
In 2525, Wallace was transferring Dr. Halsey and the SPARTAN-IIs to the Damascus Testing Facility on Chi Ceti for the Spartans to receive their MJOLNIR armor. However, while the Spartans were still aboard on the Commonwealth, a ship was detected at extreme range. Though Dr. Halsey desired that they go to battle stations, Wallace denounced it as unnecessary because he had no evidence that anyone could navigate through Slipspace accurately enough for an intrasystem jump. Captain Wallace eventually complied after further protest from Dr. Halsey, who told Wallace of the Covenant's intrasystem jump at Harvest. The captain obeyed Halsey's pleas, ordering all hands to battle stations and reactors to 90 percent.
The Covenant performed an intrasystem jump three kilometers off the Commonwealth, and the ship fired its pulse lasers and overloaded the ship's AI core. Wallace then ordered all Archer missile pods from A through F to fire. Out of the 180 Archer missiles fired, approximately 90 hit. However, the Covenant ship was completely undamaged because of its energy shields. Following this, Wallace decided to fire the main weapon of the ship: the MAC. After firing two MAC rounds, the hostile ship was still intact. While the Commonwealth was charging the second round for the MAC, the Covenant ship was similarly charging its second round of pulse laser fire. The Covenant's second burst of laser fire destroyed most of the Commonwealth, decks two through seven in section one and all port armor were melted. The MAC rounds were also destroyed. Taking Dr Halsey's advice, the Captain ordered all crew not in the bridge to put on respirator packs, and then depressurizing everywhere in the ship except the bridge in order to put out the flames caused by the laser. He then sent out all the Longswords in order to gain some more time. Ultimately, the Longswords were all destroyed after Wallace ordered the Commonwealth to fire one of its Shiva-class nuclear missiles at the Covenant ship. The Captain landed the Spartans and the doctor to receive their armor. Meanwhile, the Commonwealth acted as bait in case the Covenant ship returned.
Finally, in a last attempt to destroy the Covenant ship once and for all, Dr. Halsey allowed the Spartans to board the ship and plant nuclear warheads. Only three SPARTAN-IIs made it aboard: Samuel-034, Kelly-087, and John-117. However, in the process, Samuel was lost after his suit was ruptured by Covenant small arms plasma fire. Despite this setback, the three Spartans were able to set the warheads and destroy the Covenant ship with John-117 and Kelly-087 making it back to the Commonwealth.
Personality and traits
Although an extremely capable tactical officer, Wallace was a rather by-the-book tactician and did not enjoy having civilians on his bridge, at least civilians as vocal in military tactics in combat conditions as Dr. Halsey. Although reluctant to sacrifice his Longswords and their pilots, he gave the order so that the Commonwealth would accomplish its mission, acknowledging that the recovery of the MJOLNIR armor on Chi Ceti was worth their sacrifices.
List of appearances