Dark Knight

From the Super Mario Wiki

A Dark Knight is a class of characters that originated from the Final Fantasy series. Other classes from the series include White Mage, Black Mage, and Ninja, all of which appeared in the Mario-Final Fantasy crossover game Mario Hoops 3-on-3. The Dark Knight class, on the other hand, has only appeared in Super Mario RPG: Legend of the Seven Stars, another Mario game developed by Square-Enix. In the game, the only known representative of this class is Culex, a Dark Knight from the dimension of Vanda. Culex's identification with the Dark Knight class is one of many allusions the character has to the Final Fantasy series.