Type 4 Heavy
In my opinion the only Tier 9 Super Heavy worthy of making the list, the Type 4 Heavy is truly like none of its competition. With at least 250mm effective armor covering the entire front of the tank, while being subject to no weak spots (at least not until Update 9.20), the Type 4 Heavy can dominate the vast majority of tanks it’ll meet in a frontal engagement.
Even higher tiers will have difficulty fighting against its huge calibre HE gun, with its astounding 1100 or 1400 damage per shot depending on whether you choose to fire standard or ‘premium’ high explosive. This translates to crippling splash damage even when you don’t penetrate the most well armored of targets, accompanied by module damage galore.
Be careful with your positioning and who you pick fights with, though – if you’re met by a high penetration Tank Destroyer or a player armed with premium ammunition, they won’t struggle to punch holes in your flat armor profile, and it could be the case that you’re too slow to retreat.