The Four Million Year Old Veil of Mystery - S1.E7

A shadowy figure approaches Galvatron with a plan to defeat the Cybertons once and for all. At the Cybertron base, Arcee receives word that Praun, one of Seibertron's front-line defenses has come under Destron attack.

Fortress Maximus and the Headmasters go to investigate, but find only dead bodies there. Rodimus Convoy and Ultra Magnus arrive to inspect the damage, and discover some files missing. Rodimus uses the Trainbots to head into space toward Praun.

Meanwhile, Fortress Maximus and the Headmasters get trapped inside a revolving fortress and buried in the sand, while the Destron Headmasters laugh outside. The Headmasters must recall the training they received in the deserts of Master four million years ago in order to survive.

They switch heads and manage to escape, then confront the Destron Headmasters. Galvatron shows up on Astrotrain, but Rodimus arrives with the Trainbots and the Cybertrons throw the Destrons into the sand.