The NES was the premiere video game console of the 1980s, and it saw the birth of many of the industry's most popular franchises, like Super Mario Bros., The Legend of Zelda, and more. Nintendo capitalized on the success of the NES with various TV series, though not all of its hit games were adapted into Saturday morning cartoons. However, if a pitch by DIC Animation was green lit, we would've seen more NES titles turned into cartoons, including one based on Metroid where Samus was a man.
This has been revealed thanks to an auction of a former DIC Animation employee's estate. There are four pieces of artwork being sold in the auction on eBay (current bid is $630 at the time of this writing) that serve as concept art for segments that were meant to be a part of a TV show called Super Mario Bros. Power Hour. The Metroid art shows a male version of Samus, with a see-through helmet, battling a pink alien that may or may not be based on the space pirate Ridley.
Samus is often considered one of the top female gaming characters, so changing her gender for a TV show likely wouldn't have sat well with fans. However, it's unclear if DIC Animation meant to do this intentionally, or if it was genuinely unaware that Samus was female. After all, players only learn Samus's gender in the original Metroid if they beat the game, as it's not revealed by the instruction manual or stated on the back of the box.
If the Super Mario Bros. Power Hour was produced, it would have included at least three other cartoons besides Metroid. There would have also been a Double Dragon cartoon, as well as a California Games cartoon. The lineup would have been rounded out by a bizarre Castlevania cartoon concept that shows kids encountering some of the game's boss monsters. It seems the Castlevania cartoon would be taking a comedic approach to the material - a far cry from the adult-oriented Castlevania Netflix show that was eventually produced.
Unfortunately for anyone intrigued by these concepts, it seems as though the initial pitches were rejected, and so DIC Animation didn't move forward with actually animating any of their ideas. And considering the strange changes to the source material, perhaps that was for the best.