Jagdtiger was the heaviest tank of WW2. It was also a piece of junk. Built by the Germans, only 88 were built. It weighed over 70 tons. It required meticulous care and training and most broke down before combat. When used properly, it was devastating. The 128mm round could destroy vehicles even after going through buildings. Its best success was in the last week of the war when a handful destroyed a battalion of American Shermans in a single day. The Germans still surrendered the next day.
The Comet was the best British tank of WW2. Its 77mm gun fired the same ammunition as the 17 pounder gun from a shell case based on the British WW1 anti aircraft gun. The reduction in villosity did not have a too negative affect on the APDS shot and the Comet could still take on a Tiger or Panther at range.
Here is a cross section of a British Mark I tank from 1916. Designers hadn't yet solved the steering problem (slowing and speeding up the tracks) and relied on a pair of guiding wheels attached to the rear. World War 1
A great detail photo showing shell penetrations on the side of a Tiger 1 hull section with one causing a large crack from the impact and resulting explosion
The British Mark V tank was an upgraded version of the Mark IV tank, deployed in 1918 and used in action in the closing months of World War I, in the Allied intervention in the Russian Civil War on the White Russian side, and by the Red Army. Thanks to Walter Wilson's epicyclic gear steering system, it was the first British heavy tank that required only one man to steer it