Constructor Sentinels are a type of Sentinel utilized by the Forerunners in the Halo universe. Their fuction is to construct and maintain Forerunner installations.
Design[]
Constructor Sentinels have tall and narrow chassis, relative to their overall smaller size compared to most Sentinels. They feature two primary housings, with one located directly above the other, often joined by a connecting arm. Atop their upper housing is a pair of ear-like appendages. Perhaps the most integral feature of Constructor Sentinels are their small reconstitution emitters, which can be located in its upper housing, lower housing, or between the two, depending on the variant. Each Constructor Sentinel also features a tiny smartmatter loom and a low-tier ultrascanner, as well as an impulse drive for locomotion.
Constructor Sentinels are manufactured in Ferrarius Assembler Vats within dedicated manufacturing facilities on Forerunner installations and worlds.
Operation[]
These small utility drones operate in coordinated groups to diagnose basic faults, weave minor repairs into existing Forerunner structures, and retune hard light structural elements. Vast numbers of Constructor Sentinels may cooperate with Strato-Sentinels to complete large-scale repair operations. Steward Sentinels maintain their own complement of Constructor Sentinels for repair, preventing deterioration and compromise of the much larger Sentinel. For the purpose of repair, the Constructor's primary tool is its small reconstitution emitter. The beams fired from the reconstitution emitters can also be used to interact with Forerunner technology, allowing them to open Cryptums or lower the shields on pistons. The latter functionality allows the Constructor Sentinels to access the tunnel networks built within Sentinel Walls. Although low in power output, one of these beams can cause harm if an organism if its crosses the beam's path.
One or more Constructors will often be summoned if something within their facility is damaged. Once attracted, they appear to require little prompting to follow someone seeking their assistance. In one instance, a member of a Spartan-IV fireteam simply had to state that they had a task for a Constructor to get it to follow them, with no other obvious methods of coercion being used. Constructors can be programmed for other tasks, such as awakening a Guardian Custode, with little difficulty, being reprogrammed within minutes.
Constructors can also play the role of a security grid. When a Constructor is attacked, a signal is automatically sent to Sentinel emitters to begin deploying Aggressors. For this reason, they form an excellent security perimeter. However, with no weapons systems of their own, the Constructors must rely on Aggressors when threatened.
Game appearances[]
Halo 2[]
Constructors make their first appearance in the Halo 2 level Sacred Icon, exactly beside where Thel 'Vadamee stands after he is dropped off from his Phantom. They are repairing the destroyed edge and will leave after a while, or if the Arbiter approaches them. Attacking them will result in being attacked by Aggressors. In the level Quarantine Zone, they appear at the end of the level when the player fights the Flood-controlled Scorpion and Wraiths along with many Flood combat forms using Covenant Ghosts and two Enforcers fight against the Flood near a downed UNSC Pelican dropship. If the player watches one of the large and deep trenches, a large cloud of Constructors can be seen flying off into the sky.
Halo 3[]
In Halo 3, they appear in the level The Ark, where they are seen inside Forerunner structures, including inside the wall to the Cartographer and the map room itself. They can be also found in the multiplayer maps of Isolation and Construct, where they can be seen flying around in the distance. With the addition of the Halo Online multiplayer map Edge to the Halo: The Master Chief Collection, a flock of Constructors can be found maintaining the databanks in the rear of the Forerunner structure where the map is set.
Halo 5: Guardians[]
In Halo 5: Guardians, Constructors play a significant role in the campaign. In the level Unconfirmed, Fireteam Osiris encountered Constructors in the mines on Meridian near where the Guardian was. Though the team noted that the Constructors were similar in design to a Monitor, they were non-communicative and uninterested in the humans, so Jameson Locke ordered his team to keep an eye on the Constructors but to otherwise ignore them. Later, in the level Enemy Lines, Fireteam Osiris is tasked with acquiring a Constructor in order to activate the Guardian on Sanghelios. Osiris is able to find one in a support facility for the Guardian, attracting its attention by damaging a terminal in the facility. Dr. Catherine Halsey is then able to use Forerunner technology in the area to program the Constructor with the recording made of the Guardian on Meridian. Though Halsey thought it would take hours to days, the Constructor is programmed quickly and flies off to awaken the Guardian. In the final mission Guardians, Genesis Monitor 031 Exuberant Witness summons a swarm of Constructors to retrieve the Cryptum that Blue Team was trapped in by Cortana after Osiris manages to restore control over Genesis to Exuberant Witness. Under the control of Exuberant Witness, they use their beams to open the Cryptum and free the Spartans of Blue Team.