Bionatops from the vintage Masters of the Universe original series toy line.

Canon

Bionatops from the Masters of the Universe promotional art

Bionatops was a gigantic cyborg dinosaur resembling a triceratops. It lived in Preternia and was conjured by the Sorceress to carry He-Man into combat during the Preternian era. Bionatops had a gun mounted atop its horns which fired intense power rays. Bionatops was a natural enemy to Tyrantisaurus Rex.

Bionatops from the Masters of the Universe Classics Mini Comic

In the MOTU Classics canon, Bionotops was infected with the Techno-Organic Virus, which gave it the ability to generate cybernetic weaponry. After He-Man rescued it from Snake Men hunters in Preternia, it became his steed in Eternia’s distant past and returned with him to his own time. The Bionotops joined the Masters of the Universe during the Second Ultimate Battleground. When Skeletor received a fatal blow from the dying Hordak, he absorbed the Bionotops’s Techno-Organic Virus to transform himself into a magical cyborg.

According to the Grayskull Wiki, The Powers of Grayskull was a spinoff from the Masters of the Universe brand. Beginning in 1987, it was intended to show the prehistory of Eternia. However, the line was aborted early, and very few products were ever released.