Hello! I just have 2 simple questions.
1. During my session on Sunday, I had a player cause 12 stress on the Bridge Troll. The stress bar I think only has a stress count of 10. Since he went over, is that an automatic KO? I want to assume no and that they did that for printing sake.
Story: Wizard Brawler went to attack with Fists (+4) and roll +4 and +1 for hitting trolls. Troll defended with Fists and rolled a -3 for a total of +1. In addition to the +7, he had Weapon:5 (due to lots of strength stats) for a grand total of 13 stress hits, or 12 stress points.
I'm not quite following your math here, but if an attack deals more stress than the highest available stress box, the target has two options. Either become Taken Out, the result of which is decided by the attacker. This can be anything narratively appropriate: death, knocked out, taken prisoner, whatever that has the target no longer a part of the conflict.
The other option, if the target wants to stay in the conflict, is to take one or more Consequences to reduce the stress. If in this case the highest available stress box is the tenth, and they're suffering a 12 stress hit, the troll can take a Minor Consequence to reduce the incoming stress by 2, and take the remaining 10 by checking the last stress box. If instead the troll takes a Moderate Consequence (reducing stress by 4), they instead check the 8th stress box.
Edit: As Shaft points out, if there are 10 stress boxes, there is certainly armor involved from Toughness powers, don't forget those.