The following rules apply to many aspects of the game.
This game doesn’t use fractions; if you need to round to a whole number, round up unless otherwise specified. When in doubt, resolve any ambiguity in favor of the PCs.
When a feature allows you to reroll a die, you always take the new result unless the feature specifically says otherwise.
Incoming damage means the total damage from a single attack or source, before Armor Slots are marked.
If the resolution order of multiple effects is unclear, the person in control of the effects (player or GM) decides what order to resolve them in.
Unless stated otherwise, all effects beside conditions and advantage/disadvantage can stack.
If an effect doesn’t have a listed mechanical expiration, it only ends when decided by the controlling player, the GM, or the demands of the fiction.
Unless an effect states otherwise, you can’t spend Hope or mark Stress multiple times on the same feature to increase or repeat its effects on the same roll.
If a feature allows you to affect a roll after the result has been totaled, you can use it after the GM declares whether the roll succeeds or fails, but not after the consequences unfold or another roll is made.