Head and claws: G.I. Joe Rise of Cobra Rex "The Doctor" Lewis
Torso: G.I. Joe Rise of Cobra Cobra Commander
Upper arms and lower legs: G.I. Joe 25th Anniversary Battle Armor Cobra Commander
Elbows, lower arms and upper legs: G.I. Joe 25th Anniversary B.A.T.
Helmet: G.I. Joe 25th Anniversary Major Bludd
Harness and cyber helmet: X-Men Origins Wolverine Weapon X
Backpack and ammo belt: G.I. Joe 25th Anniversary Roadblock
Arm attachments: modified Marvel Legends Showdown Dr. Octopus tentacles, modified G.I. Joe Rise of Cobra TRU exclusive Bench Press chainsaw, modified G.I. Joe ARAH Range Viper grenade launcher, modified G.I. Joe SpyTroops Roadblock chain gun, modified G.I. Joe SpyTroops Air Assault Glider missile

I'd been struggling with a way to work Overkill into my Joeverse. The idea of him as a cyborg commanding legions of androids really appealed to me, but I wanted him to have more character than that. So I started to think about how the man he was might have become the cyborg he is.

I decided that he must've been a promising Cobra Officer who did something to incur the Commander's wrath, and that his new body and assignment are actually a punishment. After that, the design came very organically.