Both PCs can roll to seize by force, if both want to. There's only one exchange of harm, but both players' choices apply to it. In that case, if both take definite hold, it's the same as if neither do.
Ah, interesting.
For going aggro, the attacker should roll the move and the defender can roll to interfere, yes.
Sorry, I forgot about interfering when I posted. We had a Hocus in the group who had
Seeing Souls and liked marking experience, so we know
all about interfering. ;-)
Acting under fire is a little bit iffier, since it has the potential to nullify the other player's move outright and you shouldn't let it do that. I use it only when the defender gets the initiative (not a technical term) on the attacker. Like, you go aggro on me, I force your hand and suck it up, I take the harm, and then maybe I can act under fire to get into hand range.
Make sense?
I guess this is the part where my lack of system mastery shows. In that instance, would
act under fire allow you to make the hand range attack, or do you have to follow that roll up with a separate move like
seize by force?
That kind of raises a similar question of: Can
act under fire be used offensively?
Also, I'm sure you get tired of hearing it lumpley, but it's pretty awesome that you're so active in the community here and give so much firsthand feedback about your game (which is also pretty awesome by the way). Thanks! :-)