From Halopedia, the Halo wiki
Universe and lore
The Sabre is an archetypal fighter jet. It moves fast, with extensive damage capabilities, and features an aerodynamic frame.
There are several direct counterparts to the Sabre. In Halo: Reach, the Seraph and Space Banshee fill very similar roles on the Covenant side. The Seraph is a usable vehicle and operates almost exactly the same, though with damage and shielding differences.
Like other vehicles in the Halo games, the Sabre is piloted from third-person view. The heads-up display, located near the center of the screen, shows the weapon currently in use, thruster heat, as well as the hull and shield integrity of the Sabre. Enemy ships are identified by type and highlighted with a distance marker once the targeting reticle is moved to them. The HUD is slightly different depending on the weapon used at the time. It has two weapons, an auto cannon and a set of lock-on missiles. It also has energy shielding, a rarity among vehicles.
Pitch and direction change is controlled by the right thumbstick, while the left stick controls speed. However, if the player holds down the Right Bumper, a few changes are made. The auto-level functionality is disabled and left and right on the left thumbstick give full control over roll. This was a function that was initially always enabled and was cut during testing, only to be re-instated at the very last minute by holding the RB button down, and so is not mentioned in the manual, the official guide, or even within the game itself. The Sabre also has a boost function, which uses its wing-mounted thrusters. This fills up the thruster heat bar,which needs to cool down after continuous usage. A variety of maneuvers such as aileron rolls - often misidentified as 'barrel rolls' - and Immelmann turns can be performed by using the left bumper. The weapon in use can be switched between the machine guns and missiles with the Y button. The autocannons have an additional reticle leading the target, and the missiles can lock-on to enemy ships.
In Halo: Reach, crucial aspects of astrodynamics are overlooked for the sake of gameplay. For example, when thrust is cut, the Sabre no longer maintains a constant velocity. In reality, a spacecraft's momentum would propel it forward indefinitely, as friction is not present.
The Sabre is usable only in the space combat segment of the level Long Night of Solace. It is used after the launch sequence until landing on the upper pad of the Covenant corvette. After that, it isn't used again.
It is possible for the player to ram the Sabre into an enemy Seraph or Banshee and destroy it. This will award the player the Splatter Medal. Interestingly, colliding with or ramming a Covenant drop pod will destroy a fully-shielded Sabre and kill the player, despite the pod's small size. The death will register as "Collision Damage" and the player will receive a "Collision Damage" kill, but will not receive a splatter medal.
Bungie initially experimented with adding the Sabre into multiplayer, though the vehicle only appears in the campaign level Long Night of Solace in the final game due to balance issues. The vehicle was later implemented alongside a number of new items onto the Forge palettes of Forge World and Tempest for the inclusion of Halo: Reach in Halo: The Master Chief Collection.
List of appearances