The Zuikaku was seen as one of the best-balanced aircraft carriers in the Pacific War. Commissioned in September 1941, she had been planned after the Japanese exit from the Washington Naval Treaty in 1936 and was as such not subject to some of the limitations it imposed, being built in-line with Navy demands. Together with her sister ship the Shokaku, she formed Carrier Division 5 and took part in the Pearl Harbor attacks of December 8, 1941, during which all of her aircraft made it back. In April 1942 she would sink the HMS Hermes in the Indian Ocean and that May she accounted for the USS Lexington in the Battle of the Coral Sea. Thereafter she served in fighting around the Solomon Islands and the South Pacific, before meeting her end at the Battle of Leyte Gulf in October 1944.