Runes

Most magic weapons and armor gain their enhancements from potent eldritch runes etched into them. These runes allow for in-depth customization of items.

Runes must be physically engraved on items through a special process to convey their effects. They take two forms: fundamental runes and property runes. Fundamental runes offer the most basic and essential benefits: a weapon potency rune adds a bonus to a weapon’s attack rolls, and the striking rune adds extra weapon damage dice. An armor potency rune increases the armor’s item bonus to AC, and the resilient rune grants a bonus to the wearer’s saving throws. Property runes, by contrast, grant more varied effects—typically powers that are constant while the armor is worn or that take effect each time the weapon is used, such as a rune that grants energy resistance or one that adds fire damage to a weapon’s attacks.

The number of property runes a weapon or armor can have is equal to the value of its potency rune. A +1 weapon can have one property rune, but it could hold another if the +1 weapon potency rune were upgraded to a +2 weapon potency rune. Since the striking and resilient runes are fundamental runes, they don’t count against this limit.

An item with runes is typically referred to by the value of its potency rune, followed by any other fundamental runes, then the names of any property runes, and ends with the name of the base item. For example, you might have a +1 longsword or +2 greater resilient fire-resistant chain mail.

Rune-etched armor and weapons have the same Bulk and general characteristics as the non-magical version unless noted otherwise. The level of an item with runes etched onto it is equal to the highest level among the base item and all runes etched on it; therefore, a +1 striking mace (a 4th-level item) with a disrupting rune (a 5th-level rune) would be a 5th-level item.

Each rune can be etched into a specific type of armor or weapon, as indicated in the Usage entry of the rune’s stat block. Explorer’s clothing can have armor runes etched on it even though it’s not armor, but because it’s not in the light, medium, or heavy armor category, it can’t have runes requiring any of those categories.

Investiture

If a suit of armor has any runes, it has the invested trait, requiring you to invest it to get its magical benefits.

Rune Formulas

The Price of a rune’s formula is the same as the Price of a formula for an item of the same level; it can be acquired in the same way as an item formula (described on page 293).

The Etching Process

Etching a rune on an item follows the same process as using the Craft activity to make an item. You must have the formula for the rune, the item you’re adding the rune to must be in your possession throughout the etching process, and you must meet any special Craft Requirements of the rune. The rune has no effect until you complete the Craft activity. You can etch only one rune at a time.

Transferring Runes

You can transfer runes between one item and another, including a runestone (page 571). This also uses the Craft activity. This lets you either move one rune from one item to another or swap a rune on one item with a rune on the other item. To swap, the runes must be of the same form (fundamental or property).

If an item can have two or more property runes, you decide which runes to swap and which to leave when transferring. If you attempt to transfer a rune to an item that can’t accept it, such as transferring a melee weapon rune to a ranged weapon, you get an automatic critical failure on your Crafting check. If you transfer a potency rune, you might end up with property runes on an item that can’t benefit from them. These property runes go dormant until transferred to an item with the necessary potency rune or until you etch the appropriate potency rune on the item bearing them.

The DC of the Crafting check to transfer a rune is determined by the item level of the rune being transferred, and the Price of the transfer is 10% of the rune’s Price, unless transferring from a runestone, which is free. If you’re swapping, use the higher level and higher Price between the two runes to determine these values. It takes 1 day (instead of the 4 days usually needed to Craft) to transfer a rune or swap a pair of runes, and you can continue to work over additional days to get a discount, as usual with Craft.

Fundamental Runes

Four fundamental runes produce the most essential magic of protection and destruction: armor potency and resilient runes for armor, and weapon potency and striking runes for weapons. A potency rune is what makes a weapon a magic weapon (page 599) or armor magic armor (page 556).

An item can have only one fundamental rune of each type, though etching a stronger rune can upgrade an existing rune to the more powerful version (as described in each rune’s entry). As you level up, you typically alternate between increasing an item’s potency rune and its striking or resilient rune when you can afford to.

Fundamental Armor Runes

Fundamental Weapon Runes

Property Runes

Property runes add special abilities to armor or a weapon in addition to the item’s fundamental runes. If a suit of armor or a weapon has multiple etchings of the same rune, only the highest-level one applies. You can upgrade a property rune to a higher-level type of that rune in the same way you would upgrade a fundamental rune.

Rune abilities that must be activated follow the rules for activating magic items on page 532.

Armor Property Runes

Weapon Property Runes