Commercial bumper

Commercial bumpers are short segments used to mark the start and end of a commercial segment during a television show. They have been used in many Transformers cartoons.

Generation 1
The original Transformers cartoon featured a rotating series of commercial bumpers, which changed by season. The music for all seasons remained the same, however, with Victor Caroli narrating "The Transformers will return after these messages" and "We now return to The Transformers", while a character transformed.

1984
The Transformers will return:
 * Optimus Prime transforms to robot mode.
 * Jazz drives out from behind an Autobot symbol, spins out while transforming to robot mode, and backs off-screen while firing.

We now return to the Transformers:
 * Starscream flies over Earth, transforms to robot mode and lands.
 * Laserbeak flies under cam in cassette mode; a passing Decepticon symbol hides his transformation to condor mode.

1985
The Season Two commercial bumpers are distinguished by their bright, solid-color backgrounds.

The Transformers will return:
 * Cosmos transforms and lands on an upside-down planetoid, which then rotates so he's upright.
 * Omega Supreme transforms from base to robot and fires.
 * Shockwave
 * Devastator forms, raises his fists together and is enveloped by an energy glow.

We now return to the Transformers:
 * Thrust transforms to robot mode and lands.
 * Warpath transforms to tank mode and drives under the camera.
 * Astrotrain flies past in shuttle mode, changes to robot mode and fires, then changes to locomotive form and drives into the camera.
 * Grimlock changes to dino mode and uses his tail to smash a rock outcrop with the Decepticon emblem.

1986
The Transformers will return:
 * Sharkticon, transforming to shark mode and walking into the camera.
 * Rodimus Prime, dodging fire from Cyclonus before changing to vehicle mode.
 * (?) Base-mode Trypticon fires, then transforms to dinosaur mode.

We now return to the Transformers:
 * Ultra Magnus, discharging two passengers before transforming to robot mode.
 * (?) Blurr flies past camera, transforms and fires.

1987
The Transformers will return:
 * Scorponok transforms from base to scorpion, scuttles at the camera, and transforms to robot.

We now return to the Transformers:
 * Highbrow transforms from helicopter to robot over a planet.

Beast Wars
Beast Wars featured only a single, short commercial bumper, with the show's logo from the opening credits accompanied by the "BEAST WARS!" cry and a quick "We're back" as the commercials ended.

Super Link
The Japanese version of the Energon cartoon featured still shots of various characters, who would introduce themselves to the audience or give their characteristic rallying cry ("Galvatron... hyper mode!" for example.)