Com a permissão da GM, você pode usar algo de um editor de terceiros, Kobold Press. Eles têm um compêndio Novos Caminhos, originalmente destinado ao Pathfinder, mas em esta página no site deles eles afirmam que ele pode ser compatível com o 13th Age e fornecem um exemplo de capacidade de infundir setas:
Enchanted Arrows
You know a small number of words of power that you can use to infuse your arrows with magical energy. As a quick action, you may change your arrows’ damage type to fire, cold, lightning, thunder, poison or acid until the end of the encounter or you change them again. If you have the Ranger ex Cathedral Talent, you may choose holy damage as well. The arrows’ damage does not increase but you can use it to exploit vulnerabilities and avoid resistances.
Adventurer: Once per round, you deal extra damage to the target and all adjacent enemies equal to your Intelligence modifier on a natural even hit with an enchanted arrow. You may also cause such an arrow to explode on command for a non-combative purpose (creating illumination, mimicking a signal flare, etc)
Champion: Once per day, you may loose an arrow of finding. The arrow will hit its target without error ignoring distance, resistances, obstructions or even differing planes of existence. In order to loose the arrow of finding, you must be able to tie something to the arrow that represents the target (some blood, a hair, a bit of fabric, etc). If you use this ability to return an arrow that the target used to attack you, it deals double damage.
Epic: Once per day, when you hit a target with an arrow you may immediately teleport to your target’s location. You may even be “riding” the arrow, perhaps by infusing your whole essence into it when you let it go.