Blood Force Trauma

Weapon Imbuement: Blood  —  only castable / charged by weapons that "consume" blood.

A weapon's wielder can declare intent to unleash this power when making an attack. Upon success, the weapon deals an additional 1d4 of Force damage per charge.

Up to three charges can be stored at once. All held charges must be consumed at once when using this ability. Charges dissipate at the rate of 1 per long rest.