Harm

When you suffer harm you record the injury on your character sheet equal to the level suffered. Harm may be of any type - it can be a physical injury, a mental trauma or psychic attack,

You may have:

If you need to record a harm and the level is already full, you record it to the next level up.

If this means you need to record a level 4 Fatal harm, your character is retired. Work out with the Grandfather what this looks like in the fiction.

Each level has game mechanics attached to it as well:

Changes to rolls only apply if the harm can be reasonably said to effect the roll. e.g. a Lesser cut to the leg giving you -1 to rolls would not effect any rolls to do with solving a puzzle unless you think the cut would be distracting, but it would always effect how you walk or run.

Harm
3 Need help
2 Disadvantage
1 -1