Swelter and Glacius regularly teamed up with Decepticons. They were imprisoned on the Alchemor only to be freed when the ship crashed on Earth. There they teamed up with Razorpaw, despite the fact he treats them poorly. When Optimus Prime's team appeared on the hunt for Razorpaw, they attacked the former Autobot leader and even defeated Drift's Mini-Cons Jetstorm and Slipstream, but retreated when faced by the other Autobots. They brought the team of trackers to Razorpaw's attention, and accompanied him as he followed them to a military base where the pair succeeded in trapping Drift, Drift's Mini-Cons, and Sideswipe in a metal cocoon. They followed that up by taking out Optimus Prime himself, but as it turned out Optimus had been feigning. While Swelter argued with Razorpaw over the lack of appreciation he gives to him and Glacius despite the hard work they go through for him, Optimus took them out one by one. Optimus then smashed two military vehicles into Swelter and Glacius, leading them to be unconscious.
In contrast to his partner Glacius, Swelter is very hot-headed and dismissive. He sometimes doubts sharing affiliation with Razorpaw, as he hates it when Razorpaw doesn't show appreciation; and he never does.
- Swelter is a torpedo Mini-con, like Glacius. Thus, they use the same animation model as Divebomb, Axiom, and Theorem.
- Swelter can manipulate temperature. In his case- heat. This gives him elemental control over fire.
- The word swelter is related to heat. This is a nod because of Swelter's pyrokinesis.