(Wow, that’s a lot of hyphens.)
Pocket Monster is just that except it’s unofficial and not that great (but more on that later). The unlicensed platformer was made by two teams: DVS Electronic Co. for the SNES version and a team of former employees from Chuanpu for the Mega Drive iteration. It was released in 2000 when both consoles had disappeared from the hearts and minds of consumers (thanks to the Nintendo 64 and Dreamcast).
In Pocket Monster, you play the role of Pikachu as you traverse 5 side-scrolling levels and a boss at the end of each one. On the first level of the Mega Drive version, you also fight a mini-boss. According to the PM wiki page, Pikachu can jump on enemies and uses a special move to clear all the enemies on the screen, but only when their charge meter is full.
The player can start either with 3 and 5 lives and continues each, and there’s a difficulty setting in the options menu. A sequel to this game was made for the Mega Drive, Pocket Monster II. The ending is an image of some Pikachus (sic).
As Retro View remarks in the video below, the SNES version misses 2 levels and 2 bosses from the Mega Drive version but replaces them with 2 extra levels. It also has worse controls and the last boss is just a rematch with previous bosses.
Since this is a hack and not made by Game Freak, it’s not great. But it’s a remarkable attempt and if you’re interested in playing it, I’m sure you can find a ROM on the internet.
Stream the longplay below.