You only get Harm in three ways:
- You get 5 or more Stress (Vigor or Resolve) in a single hit (always the net damage after applying soak).
- Your get so much Stress after soak that your Stress Track falls to 0 (there is no “negative Stress”, it stops at 0).
- You get 1 or more points of Stress after soak while your Stress Track is already at 0.
As you see, a hit does not always need to cause 5+ damage to cause a wound. You can whittle down an opponent to close to 0 Stress, and then the last hit, that puts the Stress track to 0 would cause a Harm. And if you hit an opponent at 0 Stress again and cause after soak at least 1 damage, that causes a Harm, too.
Up to two of the above criteria can apply at the same time to cause 2 Harms in one hit:
- Causing 5+ damage in one hit and dropping the Stress Track to 0.
- Causing 5+ damage in one hit while the Stress Track is already at 0.
And there is the weapon Quality “Intense” which can add another Harm, if you already caused one on your hit.
And there is a Melee Talent “Killing Strike” that allows to spend 2 Momentum to cause another Wound on a physical attack, that already caused a Wound (or more).
So at maximum, using an Intense weapon, having the Talent Killing Strike, having 2 Momentum to spend on it, causing 5 or more Stress after soak to an opponent which was out of stress in the first place or which Stress Track fell to 0 with the current hit, you can cause 4 Wounds in one go.
That is even for PCs and Nemesis NPCs a near one-hit kill.
You can take up to 4 Harm per type:
Up to 4 physical Wounds AND up to 4 mental Trauma.
At 4 Harm (Wounds or Trauma) your character is already severely limited in actions: unable to take any Actions or Reactions without first spending a point of Fortune.
You cannot take a 5. Harm, if you would have to take a 5. Harm, you are dead (physical damage) or permanently and unrecoverably insane (mental damage).
The official character sheet is designed a bit unintuitive regarding Stress tracking - as per default, if you use the character generator, the available Stress boxes are crossed out, not the other way around as one would assume.