Tornedron is a gigantic monstrous energy creation created by Primacron and an antagonist from G1 Transformers. It is a shapeshifting energy monster that can take various forms and drain energy from various lifeforms and separate to hunt multiple prey at once and then reforming. It serves as an antagonist in "Calling all Primitives". It can also be considered as the brother of Unicron, aside from Primus.
It was voiced by Neil Ross.
Tornedron was created by Primacron by experimentation. First, he fed it fire, then an Energon cube, resulting to make Tornedron growing in size and power. Primacron then ordered it to fly across the universe and devour anything on its path. It first ate a comet, turning it into a lump of coal. It then attacks Cybertron and drains the planet of its energy, as well as the Autobots residing and guarding the area. Primacron is impressed by his creation's success, claiming it has succeeded its predecessor Unicron.
It then headed towards the moon, where the Autobot forces of Rodimus Prime and Decepticon forces of Galvatron are fighting but were left confused after the animal-themed Transformers of both sides, known as "Primitives", left the scenery due hearing a call from a mysterious voice. Tornedron drained the energy of both sides, excluding the Primitives, who have managed to left.
The Oracle, Primacron's ex-assistant, now a disembodied energy, learns of this and gathered all of the Primitives to stop it. Upon their arrival on an empty planet, the Oracle gathers them and told them about Primacron and how his new creation must be stopped.
Tornedron soon arrived on the planet and drained Trypticon, crushing Grimlock in the process. Sky Lynx attacks to avenge him, but to no avail as his weapons are useless and ended up getting drained as well. Slag then leads the remaining Dinobots while the Predacons, Terrorcons and Mini-Cassettes split up to confuse it, as well as ambushing it. However, it split into four and drained the Primitives one by one, while taking various forms. It then headed back to Primacron for his success. Unknown to Tornedron, Grimlock had actually survived being crushed and decided to avenge his Dinobot comrades as well as the other Primitives, Autobots and various lifeforms.
Upon returning, Tornedron turned against its master and creator, so it decided to drain him as well. Primacron panics and tried his best to regain control of Tornedron, only to fail. Grimlock however, arrives and throws the reverse switch, reversing Tornedron's energy polarity, killing it in the process and returning life on the galaxy. To make sure Primacron won't cause any more trouble, Grimlock destroys his computer in celebration and claimed it is the "smartest" thing that he has ever done.
- Despite being a one-shot minor villain, Tornedron is considered as one of the worst and most dangerous Transformers villains ever known, as it is known to be a far greater threat than its predecessor Unicron.