Prior to his homeworld of GoBotron becoming desolate due to the actions of the Master Renegade, the Last Engineer had experimented with Cyborg technology, replacing his own limbs and other body parts with cybernetic implants. When Gobotron was rendered virtually uninhabitable, the Last Engineer's techniques enabled him to save the survivors of his race by implanting their brains into transforming robotic bodies. The Last Engineer himself went into stasis, but would be awakened by the Guardians later in order to save the badly injured Turbo.
The Last Engineer would feature in additional fiction produced by Fun Publications, particularly in "Renegade Rhetoric." He apparently settled on the colony planet of New Earth, where he married UNECOM Lieutenant Kelly Jeffries. Unfortunately, the colony was attacked by the Master Renegade, who succeeded in stealing the Last Engineer's polymorphic inducer and was thus able to take over the colony. When both Guardians and Renegades arrived to investigate, the Master Renegade briefly aligned himself with Cy-Kill to overcome the Guardians, only to turn both factions into humans using the device. He then revealed that he had transformed the Last Engineer into a parrot using the device, which the Engineer had created to help with colonization efforts, and had put the colony's inhabitants to work building an amplifier that would be able to affect even the distant Gobotron. Unfortunately for him, the completion of the device unleashed a wave that restored the GoBots and Last Engineer to their original forms, and the Last Engineer delivered a long-anticipated knockout blow to his enemy. Upon congratulating Matt for his role in helping inspire the Guardians, the Last Engineer noted that Matthew might make an excellent name for his and Kelly's soon to be born son. The Last Engineer was also responsible for the creation of Courageous, having created four Power Suits for the Guardians to interface with his personal ship. He would later attend the signing of a peace treaty on Quartex solemnizing the three-way alliance between Earth and the heroic factions of Gobotron and Quartex, only for the ceremony to come under attack from Cy-Kill and Magmar's forces. Fortunately, the humans and their allies managed to turn the tide, and the Renegades and evil Rock Lords were handily defeated.