He-Man and his friends first encountered a Spidasaur in the Region of Flame while they were on their way to meet with the Fire People. It emerged from a lava pool and seized the Attak Trak in its jaws, but they used the vehicle's electric defense mechanism to escape. King Helios was also caught in a Spidasaur's tentacles during his fight with He-Man, and would have been eaten by it had He-Man not thrown a boulder into the beast's mouth.