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.
Japanese tanks of World War II
The Chi-To was a thirty-ton, all-welded tank with a maximum armor thickness of about 75 mm. It was much larger than the Type 97 Chi-Ha, with a longer, wider, tall chassis, supported by seven road wheels. The main armament, a Type 5 75 mm tank gun was housed in a large powered, well-armoured hexagonal gun turret. The main gun's muzzle velocity gave it an armor penetration of 75 millimeters at 1,000 meters. The tank had a Type 97 heavy tank machine gun mounted in the hull and a ball mount on the side of the turret for a second one. Two Type 4 Chi-To tanks are known to be completed prior to the end of the war. Neither of the completed tanks saw combat use.