Multitasking
( Sword and Fist: A Guidebook to Monks and Fighters, p. 62)[General]
You can perform different tasks with different limbs.
Prerequisite
Multiattack (MM2) , Improved Two-Weapon Fighting (PH) , Two-Weapon Fighting (PH) , DEX 15+, INT 13+,
Benefit
If you have four or more arms, you can use each pair of arms to perform a distinct partial action. Thus, you could attack with one or two arms while using a magic item, reloading a crossbow, or even casting a spell with two other arms.