Minor note: Powermaster Prime's animation model as used in the commercials and as a character guide for the Marvel comics is a composite of the second and third designs. The body of the model is actually a straight tracing of the concept lineart for the third version (including its different rifles and twin faux shoulder stacks), with a slightly simplified drawing of the second version's head drawn on top.
His main gimmicks, however, are the two large, blue-and-white mini-guns hidden in his back/hood, which can deploy and "weaponize" either mode. When deployed, the mini-guns swing out from his back/hood and spin, while a red LED inside his torso lights up briefly. The mini-guns swing down to the sides of his head in robot mode, and can also be deployed in vehicle mode when one manually opens the grille. Pushing down on the red lever on the center his torso (in either mode) briefly lights up the LED again and swings the mini-guns back into their hiding places.
Optimus Prime was subject to several molding and color variations in his early days. The earliest release of the figure featured larger fists, a gun with a thick, round barrel, a slightly-differently shaped gas pump, grey rockets, a grey Roller, a grey launcher in his Combat Deck, and metal plates in the floor of the Combat Deck (a holdover from the Diaclone version of the toy, to which the magnetic feet of the pilots could cling). In short order, his fists were slimmed down, the gun's barrel was pared down to a more slender form, the gas pump's shape was altered, the rockets and launcher were recast in black plastic, the metal plates were removed from the Combat Deck, and Roller's color was changed to a light blue. Along with Roller's color change, however, the Combat Deck's drone pod also became light blue, and a third running change soon followed that saw it restored to its original darker blue, and Roller changed along with it. These modified components would become the default accessories used by subsequent reissues of the Prime toy would take, though Roller stills fluctuates back and forth between grey and dark blue, depending on how show-accurate each reissue wants to be.
Smallest Transforming Transformers Convoy is the smallest fully transforming Optimus Prime toy yet. He features an accurate transformation sequence based on the original full-sized toy, but understandably has no detachable hands, and has little articulation. His sculpt is based upon his cartoon appearances. He comes with a tiny version of his laser rifle.
The first Nightwatch Optimus Prime is an extensive redeco of the previously released Leader-class Optimus Prime, replacing most of his red and blue with different shades of blue and black. In fact, he resembles the original Diaclone Powered Convoy color scheme of Generation One Ultra Magnus's truck cab. The previously blue and red flames have been replaced with silver flames, as has various other decos, replaced by copper.
Although MechTech Optimus Prime's deco is similar to the first Deluxe Class figure, some of his parts (robot shoulder flaps, chest piece/truck front) were recast in blue plastic (with the chest being painted red), and his paint applications on the pelvis, headlights & thighs are omitted. His front truck hood/backpack's deco is altered: the truck steps and the fenders were painted blue, and the gold sprays on the flame tampographs are removed, while he features additional flame tampos on both sides of his front hood, and an Autobot Insignia on his left robot shoulder. He still retains the light-piping gimmick, but cast in clear plastic, with the eyeballs being (halfheartedly) painted with clear blue. His MechTech weapon is cast in transparent orange plastic, with the exception of the scope/lever and the gun barrel, which remained opaque silver plastic due to being cast with unpaintable plastic. He also features Cyberglyphics on the left side of his vehicle mode front hood.
Hero Optimus Prime was the first new-mold Optimus Prime toy in the Generation 2 line. He transforms into a Kenworth truck of unknown model with a flatbed trailer. The truck and trailer form his robot mode, but cannot disconnect. His primary gimmick is an air-powered missile launcher that uses an air bellows attached by hose to launch his large, hollow, soft-rubber-tipped missiles. The bellows and missiles attach to his back in robot mode. His rifle plugs into the launcher's main body in truck mode.
Part of the first wave of TakaraTomy Lost Age: Movie Advanced toys, this Japanese-exclusive redeco of 2007 Transformers Protoform Optimus Prime is given a Generation 1-styled color scheme (which is also based on his appearances in IDW's Transformers: Foundation comic-book mini-series). Protoform Optimus Prime transforms into his "entry" mode. This mode somewhat resembles a cybertronic truck, with false wheels sculpted onto the sides, and Optimus Prime's trademark windows in front. His now-blue flame decoration piece fits to the back of the "vehicle", creating the illusion of a flaming comet's tail (Not sure if this was mean to represent his jetpack blast effect or his atmospheric entry heat effect, which is for no reason: entirely blue instead of hot red). The bottom of the vehicle has small wheels to roll the toy across smooth surfaces.