7. Samus (Metroid series)
This is one of those entries that you had to expect. Metroid is such a beloved franchise and Samus herself has become such an iconic character that anything incorporating Nintendo characters almost has to include her. With all the fighting she does, either in her own series or in the Super Smash Bros. games, it would nice to just have some fun once in a while, and what better way to have fun that by kart racing your fellow Nintendo mascots.
6. Professor E. Gadd (Luigi’s Mansion)
Professor Elvin Gadd is a scientist who made his debut by helping Luigi take on the ghosts in Luigi’s Mansion. He also made appearances in the Mario & Luigi series, and many of his inventions have made their way into other Mario games. There’s a vehicle in Mario Kart DS that is based on his invention, and he almost got into the game himself as a playable character, but got removed during the beta phase. His popularity has grown enough that fans want him as a racer once and for all.
5. Pit (Kid Icarus series)
Pit is one of the more underrated and underappreciated Nintendo characters. The Kid Icarus games of old are remembered fondly by the fans, but the series never reached the status where it got tons of sequels. Pit has even been neglected in the Smash Bros. series, appearing in only two of the four iterations so far. He’s definitely one of Nintendo’s second-tier characters, but that only makes the fans want him more. Pit’s status makes him both a long-shot and a realistic possibility to become a DLC character for Mario Kart 8.