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[Sanctaphrax]

Sounds workable.

[Chrono]

When a block is broken by an attack, the block's strength is still subtracted from the attack, correct?

[Tedronai]

Yes.  Unless the defense roll from the target is greater than the block strength, in which case that is subtracted instead (though the block is still broken)

[Locnil]

Do you spend FP to boost a roll before or after rolling?

[Mr. Death]

Do you spend FP to boost a roll before or after rolling?

You could do either or. Though generally, if one of my players spends a point to boost by +2, then ends up rolling all -'s, I'll let them revise their decision and use it for a reroll instead.

[GryMor]

Do you spend FP to boost a roll before or after rolling?

Strictly after, though there is nothing stopping you from pre negotiating some tags/invokes (it can bog things down though)