He is a tank specialized against pierce and missile units. If you use his missile res passive, Odin, paladin's shoulder blade, and snow-white guard he can get up to 83 missile res by himself. Pair him with Viktora using Mask of Deceipt and he will not be killed by missile units, even with def pierce. Or you can give him Golem and buff his pierce res and def to greatly reduce pierce damage. He is not supposed to be a top tier unit, but he will be very useful in certain EX quests.
let me tell u why this guy didn't show up before Kain. He is sub red mage that actually have resistannce break. He is kain chainer. usually sub redmages dont have resistance break but he and naiah are the only exeptions. For those looking for pierce chaining