A (エー, Ē, Viz: Ei, English TV: Ay) was the Third Raikage (三代目雷影, Sandaime Raikage, Literally meaning: Third Lightning Shadow) of Kumogakure, renowned to be the greatest Raikage the village has ever had.
A’s rule was punctuated by the berserk attacks of the Eight-Tails but as Kumogakure couldn’t afford to dispose of such a valuable war deterrent, he was forced to look for a suitable jinchūriki in quick succession, after the conclusion of each rampage. During one of these attacks, A fought the Eight-Tails alone, allowing his comrades to escape. Their battle resulted in A receiving a self-inflicted wound to the chest after he collapsed upon his own hand, which became his life’s shame. Since this event, he made it a personal duty to combat the Eight-Tails whenever its jinchūriki lost control, eventually making even his son become part of the group that supported him during these occurrences. He chose to seal the Eight-Tails in the Kohaku no Jōhei, resulting in his nephew’s death, hoping that someone else would have more success in controlling it.
Between these attacks, A held try-outs along with Dodai in order to search for a tag-team partner for his son, which was a long-standing tradition for the Raikage. As the exercise was seemingly going to end in failure again, he lamented the fact that this would have been unnecessary if A had an actual brother. After seeing the dummy’s head finally fall off, he looks on at B and his son, glad that they had finally found a suitable candidate. Ultimately, when Killer B was made the jinchūriki, the Eight-Tails’ rampages were at long last brought to an end.
At some point he also mentored Darui, passing the secrets of the Black Lightning technique down to just him. In his later years, during the Third Shinobi World War, he once faced an opposing force of ten thousand shinobi single-handedly for three consecutive days and nights, in order to allow his comrades to escape to safety. He eventually died in this battle and with his death, the position of Raikage was passed onto his son, A. He would, however, become renowned for his extraordinary level of durability, endurance, and strength above all else, to the point where his body itself would become reputed as the “strongest shield” (最強の盾, saikyō no tate)