Of course, there's an issue of who DECLARES what they want to re-roll first. Is the idea that both players write it down in secret or something? (Otherwise, why would both players nominate the same dice?)
True. My view is that if the conversation goes along the lines of:
Player 1: I'm going to make you reroll dice A due to parry
Player 2: Ok then, I'm going to reroll my own dice B with counter attack
Player 1: In which case, I'm not going to reroll dice A then
Player 2: Ok then, I'm not going to reroll my own dice B then
... we just have two possible outcomes:
- Player2 rerolls his dice A and B
- No-one rerolls anything
... and it's just down to Player1 to decide which of these two plays suits him best, as he's the person whose decision triggers an outcome. At worst, all situations should boil down to this kind of thing, where one player will naturally be the one who gets to choose which outcome happens.
It could get more ugly though I suppose, and working through things sequentially does avoid such difficulties.
Speaking of which, what's the current norm for someone who can force two parries on their opponent? Can they make their opponent reroll one dice, see how that turns out, and then make them reroll another dice depending how the first one turns out? That is, does anyone already play this sequentially, or is it all done at once?