Call of the Primitives

An ominous figure is crafting himself a new servant made purely of energy, named Tornedron, and is programmed to survive on energon, as well as to remain obedient to his master, unlike his older, matter-based creation, and sets his beast upon the universe, devouring a shooting star's energy in seconds flat.
 

Meanwhile, the Autobots are fighting the Decepticons and not doing too well at that, and to further make matters unsettling, the Decepticons stop firing after one of their Sweeps is shot down. This turns out to be a ruse, as they set to the skies and rain laser fire from above, though it merely gives Ultra Magnus a chance to bitch slap Cyclonus and for the Sweeps to demonstrate how terrible they are at flying, crashing into cliffs when chasing Rodimus.
 

Over on Cybertron, Kup alerts everyone about a huge bogey entering the area, Tornedron landing and crafting itself a giant glowing space spider as a physical form. The Aerialbots and Wheelie attempt to stop it, only to realise their fire only makes it grow and promptly have the energy sucked straight out of them, allowing the spider to suck all the energy out of the planet! After Cybertron is just an empty husk, it's master congratulates it for achieving so much more than it's predecessor: Unicron.

The fight is still raging on, only for Grimlock and the Dinobots to stop in their tracks and stare skyward, hearing a voice calling all of the primitives. Both sides take notice of this, so Galvatron commands the Predacons and Terrorcons to form Predaking and Abominus respectively, but they too fall victim to the beckoning voice.
 

With those forces distracted, Galvatron calls in the big guns with Trypticon entering the scene; Sky Lynx arrives to fight him, though, but neither fighter does terribly much before they're called for as well, and even Soundwave's cassettes eject by themselves to listen to the commanding voice, including two new minions, Overkill and Slugfest.

Blaster's animal cassettes are the last to be summoned, though every one of them are confused as to who calls them and from where, so they all board Trypticon while Sky Lynx guides the way. Galvatron, Cyclonus and Soundwave, the only remaining Decepticons, set off to punish the deserters, while Rodimus senses a strange energy reading approaching, which turns out to be Tornedron, who saps the energy of the planet and everyone on it!

The three Decepticons are also left as empty husks while Tornedron heads for another planet and sucks it dry as well, choosing the primitives as it's next victims. Meanwhile, Sky Lynx is leading them to where the sound is coming from, while everyone inside Trypticon start fighting after Headstrong calls Grimlock a stupid head, though their carrier shakes them up a little to quell the argument.

As they approach the planet that's summoning them, Sky Lynx notices that the space junk around them becomes older and older, meaning their destination must be pretty ancient. As they land, the creator of Tornedron is watching this and is none too happy about it, so while everyone starts fighting again after Sky Lynx suggests he shall be their commander...

A robotic ape is dispatched to the area, Grimlock approaches to see what it's up to, only for it to vanish and send him sliding down the cliff it was on a second ago. The Dinobots and Sky Lynx check on him to see if he's alright, and the big lug decides that following others would probably be a wise idea in this situation. Sky Lynx proposes they all search for the alien who brought them here, or else they'll never find out what's going on.
 

The crew enter a cave, and after a pointless scene with Razorclaw bumping into Grimlock, they find a glowing wall where the voice from earlier tells them a tale of long ago: Near the beginning of time, a chap called Primacron built some of the primitives, and as he built more his ambitions grew until he made Unicron, who intended to overthrow his creator. Unicron's attack merely left Primacron "broken, but alive," while his assistant, Oracle, was destroyed and escaped to the world they're on now.
 

As we all know, Unicron was destroyed and Primacron vowed to never make the same mistake, so he made Tornedron, which now goes about sapping the energy from everything to have as a clean slate for it's own desires. And since Primacron is so ludicrously complex and hard thinking, Oracle believes the simple instincts of the primitives is what can defeat his evil plans.

Tornedron then shows up and starts attacking Trypticon in the form of a dragon, whose attacks merely make the creature grow until it saps his energy, leaving the city-sized primitive to collapse and send his comrades fleeing for safety, though Grimlock doesn't appear to make it.

Sky Lynx then tries to fight the energy being with missiles and lasers, only to get the same treatment as Trypticon, leaving Slag to dub himself as the new leader of the Dinobots. His first course of action as leader is to command a retreat, with all four parties splitting up in different paths, though Primacron merely commands his creation to do the same, becoming four separate beings to hunt them all.

The cassettes are the first to go down at the paws of an energy tiger, putting up no fight at all, while the Predacons form Predaking to battle their opponent, a huge spiked robot, but it merely grows from the laser fire they supply it and saps them dry. The Terrorcons don't even bother forming into Abominus, preferring to spit rocks at the hydra they have to face, so it's no surprise they're sapped dry as well.

Considering how well everyone has done so far, I don't think it's even worth describing how the Dinobots fare. Elsewhere, an explosion occurs by Trypticon, revealing that Grimlock merely got trapped under rubble, and Oracle informs him that he is the only one who can save the universe, telling him to find Primacron's lair, which is in space. Meanwhile, the mad scientist getting tetchy over Tornedron not responding to his commands, which can only mean...

GET IN MAH BELLY

Tornedron has, unsurprisingly, turned against his master, and nothing Primacron does can prevent him from doing that. Grimlock arrives to save the day, and does so by laughing at what a midget Primacron is and demanding he make everything the way it was before, as well as to promise he never make any more creations. The little monkey man explains that he's tried everything...

Except for the one little switch that Grimlock tries that magically makes Tornedron harmless and restores the energy to every planet and person it drained. And with the universe saved in under a minute, Grimlock celebrates by jumping up and down and destroying the lab, much to Primacron's dismay, but the Dinobot believes this to be the smartest thing he's ever done. Aw.

Poor Laserbeak and Buzzsaw are nowhere to be seen in this episode, and Overkill and Slugfest simply vanish after they board Trypticon. =(

Primacron's assistant is never named in the episode, but the scripts provide him with the name Oracle.

Ratbat dies.

At least, it sure looks like it. After being swiped of his energy, the tiger then begins to chew on him, and since you don't see any of the cassettes (or the Predacons, Terrorcons, Decepticons or Sky Lynx for that matter) having their energy restored, you get the impression he's good as dead, but he shows up in The Return of Optimus Prime for all of thirty seconds, if that.

The Matrix of Leadership rises out of Primacron's assistant's corpse, but it goes completely unmentioned in the narration, and even the writer himself had no idea what the hell it's doing in the episode. Apparently, it's actually a spaceship, and the model for it was replaced with the Matrix, for Primus knows what reason!

I think I'm going to hell for referencing Austin Powers five years after it was funny.