Well, the character would wear no armor - thus have no protection via it. (Presumably, like mages, they might wear some form of robes.) They would wield no weapons, so they could get no benefit from them.
Also, certainly the way I envision it, the only way they use magic is to enable them to attack armored people unarmed, and not break limbs. Otherwise they wouldn't have magical abilities.
Magic resistance -- no. But I could see them as being good at evading missiles.
Also, if there's going to be people rolling around the battlefield, this is the class I could see doing it, logically and realistically.
There's particular and interesting historical reasons the martial arts developed in the Orient. Perhaps in this fantasy world, there could have been a different reason for creating a tradition of unarmed combat within its own more Western-flavored setting.
... I never played Jade Empire, but I find the Monk class one of the best things Mists of Pandaria brought to WoW.
Magic resistance is a must-- Fenris, and Templars have it because of Lyrium,
Also, with no armor, this class will be useless, cause they will die within seconds, just like Merrils
I want this art of war to be created from slaves/former slaves who had no weapons, but horned, and created martial arts to survive.
For example, a magister doesn't care abbout the well being of a slave combatant, they decide to make them fight unarmed against anything in the arenas. Win, lose, the magisters don't care, so they slaves create this as a way to survive. Or teach themselves to amuse their masters, fighting against each other, conveniently without killing, or severing each other's limbs.
To amuse their Magisters, they horn this skill. Others use it to escape. Living as fugitives, they cannot afford to get weapons, to be seen, so they hide, and sharpen this Martial Art.