The Amagi (天城, namesake: Mount Amagi) was a Japanese battlecruiser planned as part of the Imperial Japanese Navy's "Eight-Eight Fleet" programme, designed by naval engineer Yuzuru Hiraga and authorised in 1917. Laid down on 16 December 1920 at the Yokosuka Naval Yard, she was intended to be one of four Amagi class, alongside Akagi, Atago, and Takao. The design featured a lengthened Tosa-class hull with a thinner armoured belt, rearranged secondary armament, and increased power output to achieve a speed of 30 knots. Armed with ten 410 mm guns in five twin turrets, she was intended to surpass contemporary battlecruisers like HMS Hood. Construction was halted under the Washington Naval Treaty signed on 5 February 1922, when Amagi was approximately 40% complete. Plans were made to convert both Amagi and Akagi into aircraft carriers, but the Great Kantō earthquake in September 1923 caused irreparable damage to Amagi's hull while on the slipway. As a result, she was stricken from the navy list and scrapped in early 1924. The incomplete Tosa-class battleship Kaga was selected as a substitute for conversion into an aircraft carrier, while Atago and Takao were cancelled and dismantled on the slipways.

Introduced in Update "Dance of Dragons", Amagi's main feature is the exceptional firepower of 410 mm (16.1-inch) main guns, able to deal with any battleship or battlecruiser, and capable of instantly blowing up destroyers and cruisers with a single full broadside. This firepower, however, is protected by an armour scheme which can be penetrated by a number of her peers. More importantly, she's very vulnerable to aerial attacks, with her anti-air defences being symbolic at best, with just four 120 mm cannons aided by thick deck armour. Similar to other early interwar battleships, she comes equipped with torpedoes, but typically it's best to remove them from the loadout in order to avoid the risk of explosion. Overall, Amagi is an excellent, versatile warship able to dictate the balance of the battle on her own, but far from being invulnerable.