OP-T

OP-T are non-canonical (they do not appear in neither the movie nor any extra material) Robots in WALL•E video game, appearing only on levels on the Axiom, though not on lower levels. They serve primarily as a type of scout, probably to preserve energy for Stewards. They are not aggressive and only follow Wall-E when tracking.

Description
OP-T robots are small, thin white robots with blue stripes around their body. They move or hover with what appears to be a grey ball wheel. They consist of a long rectangular "torso" and a long "head" with a laser emitter; it is connected to the base or torso with a black "neck".

The laser is blue when roaming around if Wall-E is detected however, the laser turns red and tracks him. As demonstrated in Human Highway, they are tied to certain Stewards only and therefore are unable to alert all units in a larger area to come. This is not even feasible in most situations, as Stewards sometimes are obstructed by invisible barriers. Such as the blast doors in Fixing EVE for the units in the middle room.

Behavior
They roam their designated area and if Wall-E or Eve falls in the sight of the blue laser, the bot will begin to track them. Nearby Stewards will be alarmed (either from a closed Steward Kiosk or idle ones) and come to the location of the robot. When in box form and the Stewards going away, the robot also leaves the area, which presents one way to "escape" it. The other way is to throw an Explosive Cubes on it; this is demonstrated/introduced right after the cut scene in Human Highway.

If all "connected" Stewards are deactivated, the robot will also stop working and stand still with its neck and head down. Every once in a while, it will "look" for Stewards, but not find any and resume being deactivated.

Appearance
They do not appear on Earth in any way; instead, they are introduced in the third level on the Axiom: Robot Rescue. They appear multiple times at the beginning of the next level, Human Highway. Later in the game, they are also to be found a lot in Holo-Detector Dash. In the latter, they always appear in areas leading to the different consoles controlling the springs leading to the appearance titular device. (It seems as if in the larger second area, they indeed to "tie" together with a previous room containing four Stewards).

Trivia

 * They are non-canon and the only "enemy" to have that trait.
 * They appear in three missions; all of which can be considered very long.
 * The destruction of them is first introduced in the intro of Human Highway, even though they already have appeared in the prior mission.
 * It is unknown what "OP-T" stands for. However, because they first appear in a room with beds designed for humans (oversight in the design of the Robot Rescue level), "OP" could stand for "operation" in a medical sense and the "T" could stand for "tracker"/"tracking".