Whenever you invoke a flashback, the GM sets a "stress cost" in the form of a Hit Dice Expenditure:
- 1 Stress --- An ordinary action for which you had an easy opportunity
- 2 Stress --- A complex action or unlikely opportunity
- 3+ Stress--- An elaborate action that involved special opportunities and/or contingencies
After the stress cost is paid, a flashback action is handled just like any other action. Many times a flashback won’t call for a roll at all because the character has already paid the stress cost to accomplish it. However, sometimes it will involve a Skill Check, because there’s some danger or trouble involved. Or it could involve some other kind of roll (attack, saving throw, or simple ability check) because we just need to find out how well (or how much, or how long, etc.) it went.