Raise your hand if you've heard this one before: The evil Dr. Mad has corrupted the programming of six thematic robots and has sent them out to do his bidding, each utilizing a weapon that would be suspiciously effectively against exactly of their evil kin. The only thing possibly standing in Mad's way is the new creation of the good Dr. Thane: the high-jumping, fast-dashing, laser-blasting, ability-stealing Rokko Chan!
Okay, Japanese developer King Soukutu admittedly isn't exactly trying to hide the inspirations for his retro platformer. But if Rokko Chan looks and plays like a ROM hack, then it is a very lovingly crafted one of high quality. The enemies have just the right kind of 8-bit menace, the chiptune soundtrack is eminently hummable, and the different worlds to explore are expansive with clever gimmicks to the gameplay. Certainly the difficulty is right up there with the NES brethren it seeks to emulate, which can make the thankfully-remappable controls kind of a pain, but make no mistake: Rokko Chan is mega-awesome... Oh... and starting with Hockey Man went pretty well.
If you're interested in the development of Rokko Chan, be sure to check out the Rokko Chan art book!