British late WWI battlecruiser, lead ship of the Admiral-class battlecruisers (although the rest of the class was canceled). For over 20 years HMS Hood was the largest warship in the world, and the pride of the British Empire. Due to her flagship duties she never got the chance to get various large scale upgrades and refits that she desperately needed to stay a relevant combat unit.  Hood's primary actions during her career were the cruise across world with HMS Repulse in 1923-1924, patrols during Spanish Civil War, taking part in the Operation Catapult (attack on Mers-el-Kebir after France had surrendered to Germans) during which she might have sunk French battleship Bretagne, and Battle of Denmark Strait which saw her rather explosive end after she and freshly commissioned battleship HMS Prince of Wales engaged German battleship Bismarck and heavy cruiser Prinz Eugen.

While popular among the British public and the symbol of British Empire during the interwar years HMS Hood was however a rather flawed ship; her hasty up-armoring after the Battle of Jutland had left her with both rather obsolete armor scheme and several thousand tons overweight, this made HMS Hood rather wet ship (especially in harsh North Atlantic waters) and during her whole career Hood was plagued with unusually high rates of tuberculosis infections among her crew when compared to other Royal Navy vessels. Hood was also the reason why during WNT Britain was only allowed to build 2 battleships with 16" guns (the ratio of post-Jutland capital ships being 3-3-2 between USA, UK, and Japan).
hms hood