Heavy tank
The Char 2C was one of the largest tanks ever produced. At the start of World War II, France and the Soviet Union were the only countries to have inventories of heavy tanks, such as the Char B1, T-35, and KV-1. The Matilda II was designed under the British infantry tank concept which is similar to the heavy tank having thick armor and weighing more than their other tanks. It’s usually separate because they have less firepower with their cruiser tanks (comparable to mediums) at the time having the same main armament but more machine guns. Later war examples were the German Tiger I and II, as well as the Soviet IS series. Note that "heavy" versus "medium" is more a question of tactical roles than weight; the Panther, for example, was a "medium" tank that outweighed most Allied "heavy" tanks.
Tank destroyer battalion (United States)
The final tank destroyer to enter service was the M36. This was a development of the M10 hull with a new turret mounting a 90 mm high-velocity gun, the most powerful anti-tank weapon which would be carried by American forces in Europe. A prototype was originally constructed in 1942, as an experiment, and the design was standardized in June 1944. In July, the European command requested that all M10 battalions be converted to M36s, and the first vehicles reached the front lines in September. It proved more than capable of countering heavy tanks – it was recorded as disabling a Panther tank at 3,200 yards – and its roots in the M10 meant that it possessed greater survivability than the M18. A modification of the M18 upgunned to 90mm was never approved for series production.