Give an item a trait: the trait's defaults and the given data are put on the item (the same object, not a copy), and it is added to the item's has map.
The item which gains the trait.
The name of the trait.
The data the trait puts on the item.
The same item, now with the trait.
Give an item a trait: the trait's defaults and the given data are put on the item (the same object, not a copy), and it is added to the item's has map.