Updated Trepan's concept art finally!
Text based on the original text I made when creating him in 2021:
I had no idea what he transformed into in IDW, so I made the decision to make him a two-wheeler since I wanted him to be a bit fragile and meek.
Trepan is the same race as Arcee. Other two-wheelers in the game will include Flamewar and Ransack.
I'm not the type to think boob plates only go on she/her robots. If it's just metal and Trepan is based on Arcee, he's also getting boobs.
For some reason, Trepan never used his goggles in IDW. So I made my Trepan far-sighted and he uses glasses when reading or operating.
I gave Trepan orange pupils because I wanted him to have a sharper gaze. He is meant to be a very suspicious character so the reader wants to attack him.
I did not think that mnemosurgery would fit in Transformers: Prime because it would defeat the purpose of the cortical psychic patch. I gave him scalpels in his fingers instead of needles (now he's Overlord's cat).
In the past, Trepan was Cybertron's top brain surgeon. He became friends with Froid as they both shared interest in understanding how the mind worked.
Trepan is a non-combatant medic. I made up this concept based on First Aid in G1. In Mercy, non-combatant medics are bound by oath to treat any injured bot no matter their faction. They cannot fight in battles. So Ratchet is not one of these. Anyone wearing the medic mark instead of an insignia is one of these non-combatant medics. This mark comes from Pharma's wings and First Aid's shoulder in IDW.
Non-combatant medics stay with the Autobots because Decepticons simply don't allow for medics that don't fight and would treat Autobots. However, Trepan is an exception permitted by Overlord. Trepan used to be an Autobot non-combatant medic before switching sides for reasons unknown.