Alpha-Nine

Alpha-Nine was a small team of UNSC Marine Orbital Drop Shock Troopers under the command of Gunnery Sergeant Edward Buck. The team's roster changed drastically over the Human-Covenant War and the post-war era, with the remnants eventually becoming Spartan-IV supersoldiers within a single fireteam.

Squad roster
Former
 * Captain Veronica Dare - An Office of Naval Intelligence operative who assumed command of the squad during the mission to New Mombasa. She used the team for ONI's operations on several occasions.
 * Gunnery Sergeant Edward Buck - A Marine staff non-commissioned officer until the team's initiation into the SPARTAN-IV program.
 * Corporal Taylor "Dutch" Miles - The team's heavy weapons specialist during the Battle of Earth and subsequent conflicts until 2554.
 * Lance Corporal Kojo "Romeo" Agu - The squad's marksman.
 * Lance Corporal J.D. "Rookie" - The newest member of the squad by the Battle of Earth.
 * Private First Class Michael "Mickey" Crespo - The squad's explosive ordnance expert and unofficial pilot.
 * Baruti "Gramps" Komen - The oldest member until his death during the Fall of Reach.
 * "Gogo" Gomez - One of the original members. Served during the Battle of Sargasso.
 * "Daughter" Svensdottir - One of the original members. Served during the Battle of Sargasso.
 * "Sam" Samrat - One of the original members. Served during the Battle of Sargasso.

Battle of Sargasso
During the battle on Sargasso, ONI tasked Alpha-Nine—then composed of Buck, Gomez, Svensdottir and Samrat—with retrieving Lethbridge Industrial's research data before the Covenant did. As Alpha-Nine completed their mission and prepared to leave the town of Belisk, Buck overheard Sarah Palmer of Gamma-Six questioning Command about their lack of extraction. Command informed Palmer that the amount of hostiles at her position made extraction infeasible, and ordered for her to retreat to a safer location. Buck ignored ONI's orders and led his squad to rescue Palmer and Gamma-Six. By the time Alpha-Nine arrived, Palmer was the last remaining member of her squad. Together, the ODSTs eliminated the Jiralhanae, Kig-Yar, Unggoy and Banshees assaulting their position and returned back to base in a civilian truck.

Fall of Reach
Alpha-Nine was part of the 11th Shock Troops Battalion during the Covenant invasion of the planet Reach. During the battle of Reach, Baruti "Gramps" Komen was killed when a burst of plasma impacted his chest and blew out his heart. At the time of his death, the squad was merely holding a piece of ground for reasons undisclosed to them, leaving Buck to later wonder if Baruti had died for a noble cause. Komen's death left an open spot in Alpha-Nine, which was soon filled by another Shock Trooper nicknamed the Rookie.

Buck and at least two members of Alpha-Nine were present during the failed defense of New Alexandria. On August 23rd, he requested assistance from SPARTAN-B312 of NOBLE Team. After receiving assistance from the Spartan, Buck left the center of the city. He was later evacuated, escaping to Earth.

Battle of Mombasa
During the Battle of Earth, the squad—now consisting of Buck, Taylor "Dutch" Miles, Kojo "Romeo" Agu, Michael "Mickey" Crespo and the "Rookie"—was assigned to the. They were a part of a larger ODST unit with the mission to board the Prophet of Regret's flagship, Solemn Penance, by dropping in SOEIVs from low orbit. Before the drop, however, ONI officer Veronica Dare took over command of the squad in order to use them in her mission to gain access to New Mombasa's urban infrastructure artificial intelligence, the Superintendent, below the city and retrieve critically important data collected by the construct. She did not, however, reveal the new mission to the squad until mid-drop, when she ordered them to alter their course towards the city's ONI Alpha Site from where they could access the Superintendent. Dare also gave the squad clearance codes to access the Superintendent's systems, allowing them to utilize the AI for assistance, such as providing a three-dimensional map of the city.

Just as they were on their way down, the vessel jumped into slipspace, releasing a devastating shockwave and an electromagnetic pulse which disabled the squads' drop pods' electronic systems, resulting in them landing uncontrollably around the city.

Dare and Buck landed relatively close to each other. Dare's pod hatch was jammed by the hard landing, and Buck rushed to her position in order to help her. However, Covenant forces converged on Dare's position before Buck managed to reach her. When he finally discovered her pod, he found it to be empty, just as he was confronted by a mysterious Covenant creature, which was holding Dare's severely damaged helmet. Romeo appeared and killed the creature. After reviewing the situation with Romeo, Buck decided to get the squad out of the city, as they assumed Dare had been killed.

During the rest of the day, the squad regrouped, and fought the Covenant for control of the city. Finally together, minus the Rookie and Dare, the squad fought waves of incoming Covenant on the top of the NMPD Headquarters building, where Agu was injured by a Jiralhanae Chieftain. The squad then made their way to Kikowani Station, where they, upon seeing that escape through train tunnels was impossible, hijacked a Type-52 Phantom and found a way out of the city. However, Buck suddenly discovered he knew where Dare was, and ordered Crespo to turn back to the city. Meanwhile, the Rookie woke up in his pod. After wandering around the city for a while, he received a transmission from Dare, who was pinned down in the data center below the city. The Rookie made his way to the data center, and eventually found Dare. Together, they fought their way to the Superintendent's core, where they discovered a Huragok that had absorbed the Superintendent's data, namely its "Vergil" subroutine, into itself. As they prepared to leave, Buck arrived to the data center and they made their escape back to the surface. Traveling along the Waterfront Highway, they faced heavy Covenant resistance. Eventually, they were picked up by the Phantom piloted by Mickey. They left the city as it was glassed by the Covenant fleet.

Respite and redeployment
After the Battle of Mombasa, Alpha-Nine guarded the Huragok, now known as Vergil, in the ONI-appropriated Crimson Wing of the Quito Space Tether's terminus for the following weeks. Approximately one month after the battle, Sergeant Major Avery Johnson arrived to interrogate the creature. Alpha-Nine was returned to the field shortly afterward and subsequently fought in the final battles of the Covenant War, including Operation: JOINT MONITOR at some point following the Battle of Voi.

Post-war
In 2554, Alpha-Nine took part in a combat operation against the United Rebel Front during an uprising on Draco III, where the Rookie was eventually killed in action. The Rookie's death prompted Taylor Miles to retire from UNSC service.

Buck, Crespo and Agu would subsequently become Spartan-IVs, though they would continue to operate as a three-man fireteam. In 2555, they participated in a mission on the moon of Talitsa to recover Quick to Adjust and his human handler, Sadie Endesha, from a United Rebel Front facility. The mission was a success, but saw Crespo's defection to the URF and subsequent capture. Afterwards, Buck and Agu were reassigned to a Spartan fireteam at Buck's request, with Buck opting to be a member, not a leader, of the squad.

Following their service on this squad, both men were eventually again reassigned; Buck was reassigned to and acted as Spartan Commander for the Spartan contingent on the ship, and Agu was reassigned by ONI on a specialized solo mission at Concord. Afterwards, he was reassigned to a classified Spartan fireteam, while Buck was reassigned to Fireteam Osiris. Alpha-Nine itself was officially disbanded around 2558.

Trivia

 * If the player reloads their weapon, and exchange their weapon with a fellow squad member during reload animation, the squad member will reload the weapon, and if the player takes back their weapon, there will be the same amount of ammo in reserve before trading as well as a full magazine loaded. The squad member will also say a dialogue randomly chosen when the player takes control of that particular squad mate and reloads.
 * Despite every squad member being able to wield Type-25 Brute Shots in campaign and Firefight, the player cannot trade Brute Shots with them in campaign when they are controlled by AI. This is most likely because the squad and marines share the same AI program, and done for gameplay balance.
 * Though Halo: New Blood gives no indication of what Mjolnir armor variants are worn by the Spartan members of Alpha-Nine, author Matt Forbeck has implied that they continue to wear ODST armor or variants derived from it.

List of appearances

 * Halo 3: ODST
 * Halo: Reach
 * Halo: New Blood
 * Halo 5: Guardians
 * Limited Edition
 * Halo Mythos
 * Halo: Bad Blood