I have to disagree. Look at our planet. Jagged and rigid is an aspect of primitive technology. Smooth, compact, and protected is an aspect of futuristic technology. Transformers should look more advanced than what we hsve, nor technologically regressive. They have better scientists and millennia of knowledge compared to us. Smooth designs like Knight's are the only ones that make realistic sense in that context of technological progression, even as a life form.
This small version of Energon Optimus Prime was released by Kabaya as part of their DX Transformers line of candy toys. Prime transforms in the same manner as the larger Energon figures do, though his arms have to be removed at the shoulder and reinserted into his back to form truck mode. The Prime Force were sold in a separate set in the DX Transformers series, and can combine with Prime to form his Super Mode. Optimus came with a stick of gum.
Part of the third wave of Prime Cyberverse Commander Class toys, Nightwatch Optimus Prime is a redeco of Series 2 Cyberverse Optimus Prime, using the faceplate-less head sculpt that is gang-molded with the original head. His blue plastic is now gray, his smokestacks and thighs are left unpainted, he loses the Autobot insignia on his right forearm/door, and he gains yellow paint highlights for his eyes and lights, along with various other minor deco differences. Instead of the original release's cannons, he now comes with a pair of swords, which each have a pair of 3mm posts for wielding/mounting.
The TakaraTomy "Autobot Alliance" release of this toy has some significant differences, including casting the red plastic in a darker shade, making his shin and wheel joints grey rather than Hasbro's bronze, painting the Matrix of Leadership silver, and swapping out the dual energon swords for battle hooks, similar to 2010's Leader class Optimus Prime. However, due to the Japanese release retaining the Hasbro packaging, the box still advertises the dual energon swords rather than the hooks. He retains the masked face used for the Hasbro release.