“Preparation” is the term for processing the Actor’s base data, but part of that preparation is also preparing its embedded Documents, including each Item (for more info on Actor preparation, see Pre-Prepare Data).

This trigger executes before each Item in an actor is prepared, so it is ideal for modifying properties that are derived, or the result of a calculation of other properties.

Key

prePrepareItem

Arguments

args.item - The Item being prepared

Examples

Add Damage

Usage: Add +1 Damage to a weapon’s damage formula

if (args.item.type == "weapon" && args.item.weaponGroup.value == "brawling")
{
    args.item.damage.value += " + 1"
}

Notes: Remember since this runs on every Item owned by an Actor, you need to check whether an Item qualifies (based entirely on what you’re trying to achieve).

---

Set all Skill Advances to 0

Usage: Lower CN by 1 for all Spells on the Actor

if (args.item.type == "skill")
{
    args.item.system.advances.value = 0
}

Notes: This needs to use Pre-Prepare Item because the total Skill value hasn’t been calculated yet.