Devcon is a self-proclaimed bounty hunter, one of the successful few during the years of the Great War. Harboring an intense hatred of Decepticons, he spent his time fiercely hunting those who were too dangerous for the other Autobots to consider. Who he works for or who he would even collect money from for his "finds" is unknown.
It's possible for Devcon to survive for extended periods without refueling due to his incredibly efficient internal systems. This is often what allows him to outlast the efforts of his prey. The origin of his legendary tracking skills are unknown; much of his past is a mystery. In his original body, he has an arm-mounted plasma blaster and a head-mounted laser cannon. His space cruiser mode is capable of long range interstellar flight. 
He used to be friendly, courteous, and jovial, but his post-Great War career as a Peace Marshal apparently made him a bitter cynic.
Devcon left his home planet Cybertron millions of years ago, "during the Great War" (whether he was a bounty hunter at the time or became one later on is anyone's guess). He was a nice guy, dedicated to his job, but lonely.
In the Earth year of 1986, Devcon tracked Astrotrain, Dirge and Ramjet to the gambling asteroid Monacus. When the Decepticons unknowingly evaded him, he headed to a bar and ended up laying the smack down to a pair of thugs who were picking on Slizardo, the henchman of a local mob boss.
He quickly ran into Smokescreen and the alien gambler Bosch, who were down on their luck following a bad bet. Devcon was pleased by the presence of another Autobot, and sat down to drink with the pair - but Devcon's life story was interrupted by Slizardo trying to pledge his eternal loyalty to him!
After helping Smokescreen and the other Autobots on Monacus (and declining an offer to join the Autobots on Earth), Devcon flew off into space with Slizardo in tow as his new sidekick.
Universe: Featuring the Wreckers
Devcon was a jerk who ditched that Slizardo loser out an airlock first chance he got.
Hundreds of stellar cycles later, Devcon was critically damaged during the Vehicon takeover of Cybertron and forced to transfer his Spark into a Mirage drone. In need of a ride, he later snuck aboard an Autobot shuttle the Wreckers had stolen to leave Vehicon-controlled Cybertron. After attacking and defeating Packrat, Sonar, and Mol for no reason, he was confronted by the rest of the Wreckers when they were alerted to his presence. Fractyl and Arcee were also quickly dispatched before Rodimus Major could calm him down.
Devcon proceeded to sow dissent amongst the already-fractured Wreckers with his abrasive, snarky personality. After landing on Archa Nine and failing to keep the Divine Light out of the hands of the traitorous Cyclonus, the Wreckers gladly built Devcon back into his original body so he could go away.
Dreamwave comics continuity
Expanded Universe (unreleased)
At BotCon 2001, a hand-painted Vehicon Mirage, representing Devcon as seen in the Wreckers comics, was one of several future exclusives that attendees could vote to have produced for BotCon 2002. He evidently lost the vote, as the ultra-sized Jetstorm as G1 Cyclonus was produced the following year. The mock-up was put on display along with many other unmade Wreckers toys in the BotCon 2002 art room.
Among the submitted proposals for 3H Enterprises' BotCon 2005 exclusives was Energon Slugslinger (with a new head) as Devcon. Whether it actually would have been produced had 3H kept the convention license is unknown.
- Devcon's name is a play on the word "DEFCON", an acronym related to military alertness. Although unconfirmed, it is thought that, along with the embargo on the word "nuclear", the writers of the The Transformers cartoon were not allowed to use the actual word DEFCON in light of heightened Cold War tensions at the time, thus requiring a made-up soundalike word.
- Due to his transformation in "The Gambler", it would be all possible to simply repaint a Blurr figure as Devcon. Somewhere, a kitbasher is doing that.
- Devcon's inclusion in the Wreckers comic and his drastic change in personality was due to writer Rob Gerbracht being a big fan of the character, but, bizarrely, having poor recall of how Devcon was portrayed in the character's only previous fictional appearance in "The Gambler".