My friend and I are playing a game where we each have a mystic. He thinks that if his mystic attacks mine, it'll set up a chain of damage, since the mystics ability is described as retaliating with a magical blast every time a character takes damage from an attack. Since retaliate is a kind of attack, he thinks that this will damage him, which damages me, which damages him, which damages me, and so on, till one of us drops. I don't think this is the case. Thoughts?

it doesnt work like that, its just a one hit thing, you hit the mystic damage is taken, then mystics makes you take 1 point and thats the end of it

I thought that if anyone with Mystics attacks another one with Mystics, no retatiliation was taken because they share the same Team Ability, similar to KC. If anyone with KC is attacking another one with KC, they don't have to roll. right?

Not that I'm aware of...I'm pretty sure that there are no exceptions for the takers of mystic damage, yet at the same time, it should stop at one, I would think.

The Mystics retaliation damage is not an attack, so the damage from the retaliation would not trigger the Mystics TA.

The same as if your Mystic Mind Controlled a 100+ pt character and took a point of damage for it.