Rebuilt from the remains of a deactivated Scrapmetal, the Cobybot allows human Coby Hansen to finally join his Autobot friends on the battlefield. Retrofitted to allow a human pilot to control it and armed with a variety of (non-lethal) weapons and gadgets, the Cobybot is a shining example of Coby's mechanical genius.
- Japanese name: Coby Rumble
After getting his hands on a deactivated Scrapmetal chassis, Coby set to work retrofitting it, to keep from getting too depressed over his brother Bud having gone missing. He loaded it onto the colony-ship Ogygia as the Autobots prepared to make their way to the alternate universe where Gigantion was transported to.
When the Autobots discovered where the Atlantis ship had crashed, Coby infiltrated the ship in his new Cobybot, locating Bud, Jolt and Reverb, returning them to safety. Back at the ship, Coby showed off his work, even converting it to robot mode. Optimus Prime approved, and gave the machine an Autobot sigil as well.
Later, when Jolt was kidnapped by the Decepticons Ransack and Crumplezone, Coby took the Cobybot out to get the Mini-Con back. He threw a ball full of Quickmix's special instant-dry cement at their feet, giving Prime the chance to knock the Decepticons for a loop (after they'd thrown away their captive).
- Sonic Convoy (Multi-pack, 2005)
- Japanese ID number: EX-02
- A retooling (sort of, see below) and partial redeco of the Scrapmetal toy with a new head, the Cobybot transforms into a four-legged walking tank. In either mode, plugging a Cyber Planet Key into the back of its boom-crane cannon causes a removable clear-plastic blade to flip out into attack mode. The Cobybot's fists can be covered with its tank-mode walking spikes, or flat-ended "pile drivers".
- The Cobybot was normally only available as part of the "Sonic Convoy" gift set, a Japanese Toys 'R' Us exclusive, with redecos of Optimus Prime and Wing Saber. It also came -appropriately enough- with a silver-bordered Earth-style Cyber Planet Key. It should be noted that none of the toys in this set came with bio/Tech Spec cards.
- For BotCon 2006, attendees of the bonus "painting workshop" received two sets of unpainted, unassembled red Scrapmetal (to be made into versions of Rumble and Inferno). These sets included the parts to the Cobybot version, which are part of the mold-sprues of every Scrapmetal toy. However, the clear-plastic colors are different from the Cobybot proper, using the normal clear-red rather than clear-bright-green.
- The head sculpt used for the Cobybot was the original vision designed for the Scrapmetal toy. Hasbro felt the sculpt ultimately looked too heroic, and redesigned it to the more bug-like form of the final product. However, since Takara had already put work into the sculpt, they decided to use it for the exclusive.