Dino-Riders was a cartoon television series that aired in the late 1980s, primarily as a promotion to launch a new Tyco toy line. Only fourteen episodes were produced, thirteen of which were aired as part of the Marvel Action Universe. Episodes were also released as a collection of Dino-Riders VHS tapes, which are sometimes sought after as collectors' items.

The series told the story of the Valorians, a peaceful race of telepathic humans whose home planet was conquered by the Rulon Empire. 400 survivors escaped on a space ship and time traveled to prehistoric Earth using the experimental Space-Time Energy Projector (also known as the S.T.E.P). But Emperor Krulos and his lead commanders accidentally followed them into the past when a tractor beam locked onto the Valorians' ship during the time jump. Stranded in the past, the two groups recruited the planet's dinosaur population into their struggle. The Valorians used their telepathy for taming dinosaurs to ride and for domestic use. The Rulons captured dinosaurs with 'brain boxes'. These were large metal helmets which fit onto dinosaur's heads and control their brains. Both Valorians and Rulons would often fit dinosaurs with huge arrays of laser and weapon platforms, upon which people could ride, and attack one another. Battles were mostly motivated by the Rulon's desire to steal the S.T.E.P. from the Valorians, and almost always inconclusive, seldom accomplishing more for either side than restoring the status quo from the beginning of the episode.

After years of peaceful existence on the distant planet Valorie, Questar and his people were forced into battle. While fleeing from the Rulon Armada in a space cruiser, Questar ordered their STEP crystal into activation, in a desperate attempt to flee;the power of their STEP (Space-Time Energy Projection) crystal ripped a hole in the fabric of time, sending them back through time and space to prehistoric Earth. Unaware that at the same moment as their time jump, a tractor beam was attached from the Rulon's flagship, which caused it to make the jump with the Valorian ship. The evil emperor Krulos now plots to capture the STEP crystal, with his own grotesque Rulon forces. Each side uses their own methods for controlling/making friends with the Dinosaurs, the Valorians with their telepathic amulets, and the Rulons with their Brain Boxes. And so, the battle continues, in a new place and time. Written by Matt Karpowich