From publisher blurb:
Image a weapon that only responds to your hand. Armor that grows stronger as you do. Arms and armor with strange and unique abilities inherently tied to who you are. This is Blood-Forging, a rare artform practiced by the most elite craftspeople in the lands.
This supplement introduces the Blood-Forging feat, which allows master crafters to create Blood-Forged items. All Blood-Forged items gain enhancement bonuses based on the owner's total character levels, growing in power alongside their owners. In addition, each Blood-Forged item also possesses a set of unique abilities: one that unlocks when first acquired, one that grows stronger the longer it is used, and one Actualization ability that unlocks after it has been owned for five levels. The supplement includes over 40 examples of Blood-Forged weapons and armor, but players and GMs can use this supplement to come up with their own ideas as well.
In addition, this supplement includes story seeds to help GMs introduce this powerful new equipment into their campaigns. These seeds include four NPC master crafters that can teach the Blood-Forging feat to players, or craft Blood-Forged weapons and armor for them.