Fireteam Jackknife

 was the first team of SPARTAN-IV supersoldiers ever deployed. Jackknife is the most veteran of all active SPARTAN-IV units. Jackknife originally consisted of five members, although by 2558, there were only three.

Inception and Training
Five hand-picked veterans of the Great War were selected by Musa-096 and Jun-A266 in late 2552 and early 2553. The recruits: Sarah Palmer; Edward Davis; Yeong-Hao Holst; Vladimir Scruggs; and Joel Thomas, began training in early 2553. Their training included objective-based exercises and combat training against Marines.

First Deployment
Immediately following graduation from training, Jackknife was assigned to the while the vessel was still undergoing construction in the Oort Cloud. The same day the team arrived, the ship was infiltrated by a team of Insurrectionists led by the former SPARTAN-IV candidate Ilsa Zane. The Insurrectionists kidnapped the captain and disconnected Aine, the ship's A.I. from the primary mainframe. Jackknife was on S-Deck at the time and made use of the inventory's supply of second-generation MJOLNIR kits to armor up before attempting to retake the vessel. Zane noticed the SPARTANs attempting to make their way to the bridge, and vented the deck's supply of oxygen. Jackknife took cover in the captain's ready room, where Commander Lasky managed to contact Captain Del Rio. The team then split up, with Palmer and Davis climbing the exterior hull to reach the bridge undetected while Scruggs, Holst, Thomas, Lasky, and Jun made a more direct route through the ship's corridors. Palmer and Davis cleared the bridge while the rest of Jackknife subdued all remaining Insurrectionists and freed the captain. The conflict marked the first deployment of a SPARTAN-IV team and was largely considered a successful demonstration of the new class' capabilities.

First hours
At some point prior to 2555, at least two members of Jackknife were assigned to a UNSC science base on Draetheus V's moon: X50. A large Covenant fleet emerged from slipspace and engaged the UNSC Defense Fleet. Swiftly breaking through human lines, the ships began to deploy forces to X50's north pole. Both Palmer and Davis began to fight against encroaching Covenant forces, but quickly realized that massive columns of heavy enemy armor had swarmed across the arctic circle. Due to Draetheus V's intense magnetosphere, no mayday signal or warning could reach UNSC forces stationed on the planet. SPARTAN Palmer organized a squad of Marines and led them to the nearest landing pad, where a pair of Hornets extracted them. SPARTAN Palmer managed to reach UNSC Faraday Base on Draetheus V and warn forces there of the incoming Covenant threat.

Battle
The warning was delivered just in time: minutes later four s appeared several miles south of the base and began deploying heavy armor and artillery. After helping to repel the first wave of Covenant attackers, the 23rd Armored Cavalry pushed south to a massive canyon referred to as the Epsilon Expanse. SPARTAN Palmer climbed the southern wall of the canyon with a detail of Marines and destroyed the battery of super-heavy artillery providing overwatch on the canyon below. With the artillery destroyed, the 23rd Armored Cavalry took Covenant armor by surprise, destroying the entire column, although not without heavy casualties. Meanwhile, SPARTAN Davis remained on X50 and cleared a landing zone for incoming ODSTs. Recon teams had spotted Merg Vol, a known cultist leader, in X50's arctic circle, and UNSC command ordered Davis to lead a UNSC task force to a large Covenant excavation site further north. After trapping and destroying a column of Anti-Air Wraiths, Davis infiltrated Covenant lines and cleared several vantage points from which snipers could cover the excavation site. Once this was done, Davis escorted a military engineer into the heart of the excavation. Merg Vol had activated a large Forerunner monolith, which was now projected beams of energy upwards to the surface of Draetheus V itself. The engineer successfully disabled the monolith, but before Davis could lead the team away from the area, they were surrounded by hundreds of reinforcements. Davis held off against the enemy for several minutes, but ultimately was overrun and killed.

Flight
The monolith Merg Vol had activated was in fact part of a Forerunner world-builder and had begun to unmake Draetheus V, extracting raw materials from its crust and doing irreparable harm to the planet. The Covenant and UNSC stopped fighting each other as the entire planet began to crumble. Palmer helped to clear Faraday Base's vehicle depot, where several Marines had prepped a pair of Elephants for civilian and casualty evacuation. Palmer cleared a path through enemy lines to a Covenant air pad where dozens of Spirits had been abandoned. The Marines then commandeered several of these Spirits and shuttled the casualties from the surface to the remnants of the UNSC battlegroup. Palmer then took the few Marines who remained behind and captured a Phantom from the commanding officer on the planet: Parg Vol.

Return to X50
SPARTAN Palmer and the Marines then piloted the Phantom back to X50's arctic circle. Merg Vol had deployed numerous anti-aircraft guns around the monolith, forcing Palmer to set the Phantom down far from the excavation site. Leaving the Marines to defend the Phantom, Palmer systematically neutralized all of Vol's lieutenants and then attacked the cult leader himself. Despite harnessing nearby Forerunner tech for weapons and shielding, Vol was unable to defeat Palmer, who managed to cripple the Sangheili before executing him. Palmer then made her way back to the Phantom and returned to the UNSC battlegroup

First hours
On March 5th, 2558 the was personally assigned by Admiral Lord Hood on a diplomatic mission alongside the Arbiter to negotiate with the Jiralhanae Chieftain, Lydus. Jackknife accompanied the UNSC delegates to the surface alongside fireteams Majestic and Bailey. Admiral Lord Hood and Captain Lasky met Thel 'Vadam and Lydus in a large council chamber. Jackknife stood guard in the inner chamber alongside the Arbiter's personal guard, while Majestic and Bailey guarded the exterior. While the negotiations were underway, a lance of Sangheili Rangers operating under Jul 'Mdama's directions infiltrated the council chamber and killed the Arbiter's guard, placing a charge on the wall of the inner chamber. Just as Commander Palmer found one of the Arbiter's dead guards, the wall was destroyed and the Rangers open-fired on the delegates. Jackknife escorted the delegates outside where they met up with Majestic and Bailey, who were under fire from an army of Covenant. A wing of Banshees destroyed the only available evac shuttle, stranding the delegates and Jackknife on the surface. Commander Palmer managed to locate an old parts depot nearby, where the group took cover from the encroaching army, sealing the door to keep out the enemy.