If my Seyn is attacking, a what point do I have the opportunity to cancel my own attack dice to assign a face down damage card to the opponent? Does my opponent get to roll defense first? He wouldn’t, would he?

Immediately after you throw dices. So you decide before any resolve or dice modifications happen.

Should be "before any rerolls...."

It’s a dice modification. So during Seyn’s dice mod step.

Throw your red dice

Opponent mods your reds

You mod your reds *here*

Which means if you have Marksmanship, at range 1 of Howlrunner, and you’re focused, you can reroll a blank, mod a focus to a hit, hit to a Crit, then spend the Crit for her ability.

1 hour ago, Robeetou said:

Immediately after you throw dices. So you decide before any resolve or dice modifications happen.

RR Pg 10

“Spend” is a dice modification 😁 👍

Seyn card for reference:

It does indeed say 'spend' which as JBF said:

1 hour ago, JBFancourt said:

RR Pg 10

“Spend” is a dice modification 😁 👍

3 hours ago, Robeetou said:

Immediately after you throw dices. So you decide before any resolve or dice modifications happen.

Even if Seyn only said 'cancel' I still do not know where this specific idea is from...

There have been a couple topics about the best interpreted timing for open ended cancel result type abilities. Consensus leaned toward either only during the cancel results step or any time during the attack/defense (with the caveat that during cancel results is still the strategically best time)

Ok. I was out and about running errands earlier, didn’t have the card in front of me. It’s pretty straightforward. Thanks all!

12 hours ago, JBFancourt said:

RR Pg 10

“Spend” is a dice modification 😁 👍

Yes, absolutely right. And equipped with Markmanship, I modiy Seynas dice as well. I just forgot that, because my last games were in Hyperspace (marksmanship is not HS legal at the moment).

Dose her ability “HIT?”

Can I kill a stealth device with it?

Her ability does not cause the target to suffer damage, so no, Stealth device remains functional.