Balzac

Power Surging: Balzac was a mask Teigu previously wielded by an unnamed Lieutenant of the Imperial Army who was an acquaintance of Najenda's during her stint as a General.

Abilities
When worn, Balzac can tap into the wearer's body and mind and unlock their potential by 100%, giving the wearer super speed, super strength, lightning-quick agility and unparalleled intelligence. After all of the wearer's potential is unlocked, it cannot exceed that person's limits.

Its weakness, however, is that the wearer can still be defeated by someone stronger than them, such as the Lieutenant who wore Balzac last. Even with his powers fully unlocked, he was still killed by Esdeath.

Trivia

 * The Teigu's name is a possible reference to Honoré de Balzac.
 * Balzac was never properly addressed in the series. Its name and information are only found in the Akame ga Kill! Official Guidebook.

Balzac