Superheavy

Near-synonym: superheavyweight

Source: wiktionary

The superheavy tank weighed 80 tonnes and was said to be indestructible in combat.

Source: wiktionary

Near-synonym: superheavyweight

Source: wiktionary

Representative of the scope of Soviet artillery development, two types of super-heavy, self-propelled artillery pieces (a 400mm mortar and a 310mm gun) trundled across Red Square during the parade of November 1960. There is no doubt that these weapons fire an unorthodox long-range shell, or that such a shell could carry a nuclear warhead. However, with the advent of rockets and missiles on mobile launchers, and since only two of each type of these super-heavies was seen on parade, it may well be that they will never be produced and issued to troops in large numbers. Whatever their intended role, these guns clearly demonstrate the broad scope of Soviet effort in the field of weapons development.

Source: wiktionary