Robot characters have appeared in all the TimeSplitters Games. In the games, there are a few robot scenarios, such as The Machine Wars and the Robot Factory. Robots are usually under the control of a more intelligent something, such as Jacob Crow or the Machinist. In the games, robots are mostly used as war machines, so they are very capable fighters.
All robots have special in-game abilities when character abilities are turned on. For one thing, most robots are immune to fire. Also, most robots have high stamina, although other characters have this, too. Additionally, most robots are especially damaged by the ElectroTool.
There are several different robot series. The most different characteristic in each series is appearance alone, not the actual function, as almost all robots are meant as war machines. A few of them have human characteristics, such as having four limbs, a torso, and a "head".
The R-100 robots are some of the more common robots in the games. They are featured in each TimeSplitters game, with R-108 in TimeSplitters 1, R-109 in TimeSplitters 2, and R-110 in TimeSplitters Future Perfect. These are some of the more bulky and powerful robots. Due to each of these robots' roles in their respective story missions, this series is thought of as an ally, although they are actually enemies in the games.
The Gretel series feature Gretel, Gretel Mk II, and Gretel Mk III. These are actually some of the good robots, and they are on the humans' side. However, it is possible that they work for Jacob Crow's company UltraNet, as implied in the briefing for the Robot Factory level, making them "evil" characters. Additionally, these appear to be the only "female" robots in the entire series.
The PROMETHEUS series are sort of basic battle droid-style robots. Like most robots, these are also against humanity. There are two PROMETHEUS models in the games, PROMETHEUS SD/7 and PROMETHEUS SK/8. They sort of resemble bulkier versions of the INSETICK series. The PROMETHEUS robots are only featured in TSFP. As with all UltraNet robots, "SD" is the standard edition, whereas "SK" has extra features. Though not featured among the characters in-game, there are some darker-coloured PROMETHEUS robots that appear only in the Machine Wars level. Why this one was not included in arcade in place of one of - or in addition to - the other two, is not known.
INSETICK robots come in two models, INSETICK SD/12 and INSETICK SK/10. INSETICK models are skinnier and shorter than the R-100 and PROMETHEUS series. Some speculate that, when looking at an INSETICK from the back, they resemble a Reaper Splitter. As with all UltraNet robots, "SD" is the standard edition, whereas "SK" has extra features.
The Machinist owns a Robot Factory, where he produces several types of robots, mainly ChassisBots and SentryBots. Both of these are black with red vision cameras. The ChassisBots are skinny, and more like foot-soldiers. The SentryBots are large and bulky, more like tanks.
U-Genix used a variety of security droids to guard their offices and labs in Breaking and Entering and You Genius, U-Genix, but many of them, like the Machinist's robots, are not available as playable characters. However, one robot - SecuriDroid XP - was playable and listed as a character from the 2054 time period, even though he does not appear in any Story missions. One other robot of note, is an early prototype of a R-100 Series robot, that leads Sgt. Cortez to UltraNet during The Machine Wars.
Strudel, a small robotic cat owned by Khallos, is the protagonist of the cat racing challenges. However, he is unplayable in arcade mode, except for when you add him in TimeSplitters Future Perfect Mapmaker as an item. He is briefly playable in The Khallos Express.
Despite Robert One-Oh-Seven's name and appearance, he is not a robot of the R-100 Series, and shares no attributes with other robots. Instead, he is a deranged human who thinks he is a robot living at the time of the Machine Wars, and seemingly fights for humanity, as judged by his biography in the games and the challenge Balls of Steel, which states that he cannot harm humans.
- Robofish is the only robot that appears in more than one game (all three).
- In arcade custom, all robots seem to be waterproof, unless falling into deep bodies of water, like in village or Venice.
- In TSFP, all robots, excluding Prison Officer, use a unique death animation. The only time they don't use it is through explosion via injector or zeppelin's propellers, or falling out of bounds.