Nintendo had plans for a Metroid and Castlevania cartoon years ago, but they would have been unrecognizable from the games that inspired them.
The evidence was discovered at an estate sale for a former DIC Animation City employee. At the sale, buyers discovered promo art for four Nintendo cartoons that were never made. All four were labeled as part of the Super Mario Bros. Power Hour, indicating they would have been an expansion or sequel to The Super Mario Bros. Super Show!, which included short animation for both the Super Mario Bros. and Legend of Zelda series.
The four shows were Double Dragon, California Sports, Castlevania and Metroid. Double Dragon and California Sports look like relatively faithful adaptations, but Castlevania and Metroid appear to be drastically different.
Holy shit. Someone just put up promo art for The Super Mario Bros Power Hour on eBay! These were concepts for other video game based cartoons to run along side Super Mario Bros 3. None of these ever got past the concept phase. pic.twitter.com/eIFft21T3u— Tanooki Joe™️ (@TanookiKuribo) May 7, 2019
The Castlevania art features recognizable monsters from the games, including Dracula, Frankenstein's monster, Medusa, a mummy and Death. However, the picture also features two kids with a flashlight. Both parties look frightened of each other. Castlevania is a centuries-long dark fantasy epic where a family is cursed to do battle with Dracula until the year 1999, but this appears to be more of a silly monster show. Netflix's recent Castlevania adaptation, on the other hand, featured tons of gore and violence.
Metroid's art finds Samus Aran in a sci-fi setting, blasting a space alien out of an airlock, which is reminiscent of the original Alien films that inspired the games. Despite a transparent helmet, Samus's uniform otherwise resembles the original suit. However, this animated Samus is clearly a man, despite the fact that the character is a woman in the game.
DIC eventually created Captain N: The Game Master, which did include Castlevania's Simon Belmont and Metroid's Mother Brain, as well as other Nintendo characters. There is even a crossover with DIC's The Legend of Zelda series. It is possible Captain N incorporated unused concepts from these proposed series.