Just look at this screenshot, no arcane armor units and 5* units weak to magic, what the hell, how are you supposed to play that out ?
Lord of Death counts as an arcane unit to avoid getting the same ~5 units every roll. Lord of Death isn't great against 7 or 14, but it's solid against 8, 15, 18, and 20. It's the same for Gargoyle and Priestess of the Abyss. I personally think that roll is playable, but if you don't like it, that's what reroll is for.
really ? playable... all the units are weak vs magic with their armor, not only do you not get a single real arcane armor roll, but 5 of the units are directly weak towards magic...