The brainchild of First Sea Lord "Jacky" Fisher, the Invincible class were the first battlecruisers ever to be built, pioneering the design which was based around the idea of an enlarged and upgunned armoured cruiser that should have the firepower and protection to devastate enemy cruisers and raiders, yet be fast enough to outrun opposing battleships. Built between 1906 and 1909, the Invincible class formed the foundation of this new type of ship which became a key part of the ongoing Anglo-German naval arms race.
HMS Invincible was laid down on 2 April 1906, launched on 13 April 1907, and commissioned on 20 March 1909. At the start of World War I, she took part in the Battle of the Heligoland Bight, then was transferred to the West Indies, where she participated in the Battle of the Falkland Islands, destroying a German squadron consisting of obsolete battleships and light cruiser alongside her sister ship Inflexible. In February 1915, she returned to Britain, becoming the flagship of the Third Battlecruiser Squadron. During the Battle of Jutland on 31 May 1916, Invincible was sunk after a short duel with SMS Derfflinger.
Introduced in Update "Hot Tracks", HMS Invincible is presented in her 1916 refit. She is a typical representative of the large World War I-era warships in the game, with minimal AA defences and mediocre anti-torpedo protection, and generally weak armour for such a large vessel. However, as a representative of the battlecruiser class, she boasts decent mobility.