Imperial Arm

An Imperial Arm are mysterious and extremely powerful relics that exist in the Village of Akame ga Kill. They are rare, and only the strongest of warriors are able to wield them. Some have the appearance of equipment or weapons, while others seem to be living creatures. It is implied that a form of magic was used to create them. It was created by Clear Klaus and Makoto Murakumo's Ancestor.

Usage and Limitations
While the Imperial Arm give its user amazing powers, they are not almighty. It is stated that there is no Teigu that can resurrect the dead. Even if a user is strong enough to use a Teigu, it can still reject them, and a user's first impression of it affects their compatibility. The user must be compatible with the Teigu in order to wield it.

Biological Imperial Arm are shown to be capable of regenerating after serious damage, but are not indestructible; if their core is destroyed then so is the Teigu itself.

Several Imperial Arm were shown to have a hidden ability (奥の手, oku no te, lit. secret move), often referred to as "Trump Card" or "Ace in the Hole". It is said that not all Teigu have those, however, certain users can develop such abilities themselves. Usually, such moves are the most powerful, last resort ones.

If two Imperial Arm users engage in a battle, both with killing intent, one of them is certain to die. If multiple users are involved, there is a high probability of only one of them surviving.

An ironclad rule among its users is that every person can wield only one Teigu, since a single Teigu requires considerable amount of mental and physical strength in order to be controlled. According to Esdeath, if one were to use two Teigu at the same time, they would be destroyed by it. However, it is not outside the realm of possibilities to utilize two Teigu at once, should the user be compatible with both Teigu and have the physical strength to withstand the burden.

Currently, Wave has been the only one that has ever been able to use two Imperial Arms at once.