Guardian

Guardian was the first to outdo the Dinobots at being big and dumb. An automated defense of the Ark, he was reprogrammed by Shockwave to attack Autobots and fitted him with an incredibly large time bomb. After recieving a sound beating (and losing swoop), the Dinobots spent a long time trying to kill him, going so far as decapitating him - this achieved very little.

Swoop was repaired just in time to fly Guardian far from the Ark before he could detonate. Sadly he cut it far too fine, and was vaporised in the ensuing explosion.

From Teletraan I: The Transformers Wiki, a Wikia wiki.