Spinda

A few strange gimmick Pokemon have been made by Game Freak over the course of five generations of Pokemon: Castform was meant to showcase then-new weather moves and abilities, Unown was made to furnish the Ruins of Alph and create a mildly inconvenient form of code writing, Smeargle could learn every move but had pitiful stats with which to do so, and Plusle and Minun were Pikachu clones meant to represent double battles. At the very least, such Pokemon served a purpose, no matter how contrived. In comparison, Spinda seems extremely random, if you pardon the pun. It's a Pokemon with a variable sprite based on PID and... that's about it. Spinda is, to put it bluntly, a terrible Pokemon. No matter what it tries to do, it will always be held back by its abysmal stats, nearly matched by such fearsome monsters as Farfetch'd and Snorunt. For some strange reason, Game Freak had the urge to polish one of their turds and released Spinda in the Dream World with Superpower--a move Spinda literally cannot learn in any other way--to go with Contrary, allowing it to effectively gain a Bulk Up boost upon launching off a strong Fighting-type attack. Sadly, Game Freak paused the process and, evidently, forgot about it--Spinda cannot learn Superpower in BW2, which means that the surprisingly decent combination of Baton Pass, Rapid Spin, and Superpower remains illegal. In the meantime, Spinda remains a mangled mess, a useless piece of junk that nobody is ever meant to use, simply a remnant of Game Freak's caprice.