Laurel of Bloodwood has following ability:

"After rolling a Ranged attack, Laurel may spend 1 fatigue to convert any extra range she rolled into damage on a one-for-one basis."

So I do my attack roll (monster's distance are 3 spaces, rolled range is for example 6), give 1 fatique to convert range to damage (+3 damage). And now Overlord choose to use Dodge card and I have to reroll some dice. New rolled range is 4. My question is: Must I give another fatique to convert range to damage (+1 damage) or how is it?

I'd say that you can't convert fatigue until after the attack's reroll, if any. If you move too fast for the overlord to play his card, he can force you to back up and let him play it, but that cancels your first decision, and then you can choose after the reroll whether you want to spend a fatigue to use Laurel's ability or not.

The imprecision of language in Descent writing notwithstanding, I consider a reroll to be part of the "die roll" process, and so anything done "after the roll" should wait until after the re-roll (if any) too.

Antistone said:

+1

+2 for what Antistone said. All dice rolling (and re-rolling, which is generally limited in this game) must be done before effects like Laurel's are used.

It's clear... Thank a lot!