Control room

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A control room is a crucial facility featured on many Forerunner installations, most prominently those of the Halo Array. The control room of a Halo contains the installation's Core data center, and is where the Index is used to activate the ring's primary weapon. It is typically located within a pyramidal temple-like structure. These facilities are featured on other installations as well; shield worlds, for example, possess dedicated control centers for the Forerunner fleets or weapons they may contain.

Installation 03
The interior of Gamma Halo's control room resembles that of Installation 04 in general layout. It was here that John-117 defeated the Ur-Didact following the New Phoenix Incident. The Master Chief utilized the ring's activation index to manually disabled the installation's safety protocols, allowing monitor 859 Static Carillon to eject the fragment of the ring housing the control room into the planet below, seemingly incinerating the Didact in the impact but keeping the control room intact.

Installation 04
Installation 04's Control Room was a ziggurat-like structure located in a snowy chasm. The main console and Core was located within a massive spherical chamber behind a set of doors and connecting corridors. The room features a massive hologram of Installation 04 and the Threshold system in its center. Suspended in the air is a large circular catwalk.

The Master Chief reached the main console and inserted Cortana, who sent him to the installation's Flood containment facility to attempt to stop Captain Keyes from unleashing the Flood. He returned to the Control Room at the start of Two Betrayals to insert the Index as prompted by 343 Guilty Spark, but was stopped by Cortana. 343 Guilty Spark then sent Sentinels to stop the Chief. After the Chief destroyed the Sentinels, he took Cortana and left.

Installation 05
Installation 05's Control Room is located on an offshore island in a large body of water. It bears significant structural differences from Installation 04's room.

Here, the Jiralhanae Chieftain Tartarus brought Miranda Keyes to the Control Room along with 343 Guilty Spark to attempt to activate Delta Halo. He succeeded in initiating the activation sequence of the installation, but was slain by Arbiter Thel 'Vadamee and Sergeant Johnson. The Index was removed by Miranda before the weapon could fire. Upon activation of the firing sequence, the control room's central chamber reconfigured from its inert state into a three-leveled structure with a gravity lift in the middle.

Installation 04B
The Control Room for the replacement Installation 04 is a nearly identical copy of the original ring's Control Room. The temple structure has the same basic triangular shape as Installation 04's Control Room, with a long support beam running from the ground to the top of the structure. There are minor aesthetic differences, including the walkways on each level being more narrow, as well as the tower at the top being replaced by a large flat landing.

Inside the control room, the corridors and doorways are reminiscent of Installation 04, while offering minimal changes. The actual control room and control panel is scarcely different from the original. The large dome-shaped room still shows a holographic image of the Halo ring, although Threshold is missing from this image (as the ring has not been moved to that point).

The differences in design from the original Installation 04 may be due to the ring's incomplete state, as suggested by Cortana's observation, "Halo. It's so new...unfinished."

Shield World 0459
Shield World 0459's Apex Site was classified as a form of control room. This facility was an elongated platform suspended in the air high above the interior surface of the miniature Dyson sphere, surrounded by docking towers housing Forerunner dreadnoughts. At one end of the platform was a control panel which, like many Forerunner artifacts, could only be operated by a Reclaimer.

Trivia

 * The control room was first seen in the pre-Xbox Halo demo in 1999. In the video, the control room was about one-third the size of the version later seen in Halo: Combat Evolved.
 * It is most likely that the appearance of the Control Rooms differ with each Installation, since the design of the one found on Installation 04 bears little resemblance to that of Installation 05. Given that not all of the Halo rings known to have existed were built concurrently, it is possible that Installation 05's design was of an earlier or later version than that of Installation 04.

List of appearances

 * Halo: Combat Evolved
 * Halo 2
 * Halo 3
 * Halo Wars
 * Halo Legends
 * Origins
 * Halo: Combat Evolved Anniversary
 * Halo: Silentium
 * Halo: Escalation
 * Halo 2 Anniversary