Which one do you prefer and why?
P.D. I need a red tome, so Arvis might even be an option here, what do you guys suggest?
Depends.
Lyon fits well as a red Raventome user.
Julius is just a full on mage tank.
I perfer Julius, but it depends on what you need.
Edit: Of all red tome users, however, Arvis is probably the best candidate. Not as much for combat, but rather utility. Healing, Quad Ploys, AoE Special by Default, fantastic support unit.
In my opinion, Arvis is the easiest to make combat ready; Fury is all you really need, with 51/34 offenses and 36 Res, combined with Quad ploys, he can hit like a power house and can debuff some decently fast units enough to double them. I've had the best experience with him, Julius is still a great idea, and I've never had the ability to fully invest in Lyon.
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