Deployment spire

For Halo: Reach's multiplayer map, see Spire. Spires are Covenant structures that serve as bases of operation during ground engagements. They function as teleportation hubs for invading forces, and are also capable of projecting energy shields over a large radius. Covenant forces often utilize these teleportation spires during large-scale operations.

Description
The Spire consists of multiple sections: a lower section, which projects several energy beams that keep an upper section suspended high above it, as well as a floating shield-generator array. From the upper level, a large dome-like energy shield is extended to the ground. This shield is resistant to conventional weapons, and is capable of disabling any enemy vehicles that pass through it. The Spires are used to transport ground forces to the surface from a large vessel such as a supercarrier, and also appear to serve as bases and staging areas.

There are two ways to reach the top of the Spire: via the same gravity lifts that hold the upper level aloft, or off one of several lifts positioned at intervals around the Spire.

Unlike most other forward operations structure and vehicles, Spires do not have an easily accessible reactor core like Type-47 Ultra Heavy Assault Platforms or Type-38 Anti-Aircraft Cannons. The shields generated by the Spire must be deactivated manually through a control interface in the upper portion of the structure. These controls are typically manned by Sangheili Ultras.

Covenant Spires are presumably deployed from starships and dropped directly onto their intended location; this is evidenced by the nature of the only Spire ever observed at close range, Spire One. The Spire's base lay partially buried at the center of a massive crater, surrounded by blasted sand. This may have resulted from it being dropped from a great height.

Use in combat
Covenant Spires are used primarily as command posts and teleportation sites for troops. Their shields make them difficult to attack, as they can only be disabled by ground forces after they infiltrate the structure. They also presumably make effective watch-towers.

Spires also appear to be able to somehow generate a "cloaking field," similar to active camouflage. Ships above the Spire (or a network of them) can become completely invisible to both instruments and sight, as seen with the supercarrier Long Night of Solace. However, it is possible that the Long Night of Solace generated the field itself, which a ship of its size would likely be able to do, and the Spires were simply used to conceal the origin of the smaller transport and attack craft it was sending to Reach.

Background
Multiple Spires were seen during the Covenant invasion of Reach. Covenant ground forces deployed these behemoth structures to cloak the presence of a Covenant supercarrier, Long Night of Solace. One of these Spires were disabled and destroyed in a UNSC counter-offensive operation.

Trivia

 * A similar energy shield structure can be seen in the Halo Wars level Dome of Light. This structure may be an earlier version of the Spires used on Reach.
 * Strangely enough, although there are multiple lifts leading to the top of the spire, there are no "conventional" ways of getting back down. The only survivable ways of getting off of the top of the spire are to use an aircraft, jetpack, or to land on the pillar-like gravity lifts placed around the structure seemingly for this purpose. It is unlikely that the Uggnoy stationed at the top would be able to use the latter two methods, but the reason for a lack of exits may be that the operating crew of the spire is expected to stay on top of the structure until it is decommissioned or they are required elsewhere. If this were to be the case, then the design of a spire would allow troops to go to the top to defend the controls from an attacker, but would save resources on constructing a lift for personnel that could just be picked up by a phantom if they needed to be relocated.

List of appearances

 * Halo: Reach