This large metal cylinder with a heavy, serrated sword blade at one end attaches to a warforged. It fits over the hand and forearm. An armblade is a +1 bastard sword, and requires the Exotic Weapon Proficiency (bastard sword) feat to use it properly. While the weapon is attached, the warforged cannot be disarmed, but the warforged also cannot use that hand for other tasks without removing the armblade.
In addition, the wielder gains a +2 bonus on opposed attack rolls made to disarm an opponent. If the wielder uses a ready action to set an armblade against a charge, he deals double damage on a successful hit against a charging character.
Faint transmutation; CL 5th; Craft Magic Arms and Armor, heroism;
Price 2,300 gp; Weight 8 lb.
Source: Eberron Campaign Setting