Midna
Midna is one of the main protagonists in The Legend of Zelda: Twilight Princess. She stumbles across Link early in the game who had gotten himself into some serious trouble at the time. While she may come off as selfish and brash at first, Midna eventually learned to change her outlook on life and towards those who helped her. She appears mostly in her cursed form throughout the game where she looks similar to an imp with a mask covering her head.
Midna’s cursed form is one of the many playable characters in Hyrule Warriors where she relies mainly on the power of the Fused Shadow to fight. While she still retains her ability to summon Twilight portals and use magic, it has been weakened significantly. Nonetheless, she is still a formidable foe especially with her ability to manipulate her hair into a large hand. Having only one hand would become Midna’s unique characteristic in ARMS. To compensate, she could have a larger hitbox as compared to the rest of the roster and also possess the skill to knock back most attacks. For her unique ability, Midna could also come riding into the battlefield with a Twilight Wolfos that she can use to tackle the enemy for a follow-up attack. Mastering Midna would take extreme skill, but the payoff would be worth it.
