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This object exists primarily within the Sonic Underground continuity.
Information in this article may not be canonical to the storyline of the games or any other Sonic continuity.

The Sleeper is an object that appears in the Sonic Underground television series. It is a missile-like drone utilized by Dr. Robotnik to capture Freedom Fighters.



The Seekers are rather small red, orange and yellow machines that can be held in the hand. Cylinder-shaped, they have four yellow fins on the front that extend down the sides and two red rings around them. They also have four smaller fins on the rear.

Features and abilities

The Sleeper is a missile that utilizes Tritranium as a fuel source, allowing them to run for days without the need to refuel. They are also capable of free-roaming flight, and pack a lot of horsepower for their size; a single Sleeper can drag an average person around by itself.[1]

The Sleepers' main function is to release a gas that can induce sleeping, which they use to capture Freedom Fighters.[1]


The Sleepers were used by Dr. Robotnik to capture Freedom Fighters, having been designed to seek out Freedom Fighters and then put them sleep with their sleeping gas, thus making them easy picking for Robotnik's robot drones. Due to their design however, they would only run on a fuel made from Tritranium. The Sleepers proved to be a stunning success, to the point that Robotnik was able to capture and roboticize twenty-eight Freedom Fighters in a week.[1]

After discovering the Sleepers, the Sonic Underground tracked the Sleepers down to their production facility and destroyed all existing units. Afterward, they destroyed Robotnik's only source of Tritranium, thus preventing any future production of more Sleepers.[1]

See also


  1. 1.0 1.1 1.2 1.3 Hurst, Ben; Allee, Pat (18 October 1999). "Sleepers". Sonic Underground. Season 1. Episode 36. First-run syndication.
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