Umbra

Umbra, also known as the Shadowy Man, was originally meant to be the main antagonist and final boss for the Adventure Mode: The Flash Of Shadows, but was scrapped after the whole storyline was remade and it was confirmed she would be no longer appearing in the game.

The early concept stated the Umbra was an entity who possessed the power of the shadows. Not much was known about her, but she was said to have three forms. It had been said that Umbra would make an alliance with other major video game antagonists and villains in the SSF2 roster, such as Bowser, Mewtwo, Wario, and Shadow, among other guest characters who are not in the roster, such as, possibly, Dr. Eggman, and Ganondorf.

A little of her backstory was leaked from the developers: Umbra's original state throughout the story, Umbra would lead half of the Armies of Darkness, and would be commander of the CuBots. Umbra was defeated many years ago, and appeared in a weakened state. Umbra wishes to take back her power and will stop at nothing to do it, though no one is sure what her true powers are.

Trivia

 * Originally, Umbra was supposed to be a male character. It was suggested, however, to make him a female character, instead.
 * Umbra's design as a female character was revealed on April Fools 2020.