The Ussr tech tree is by far the most different tech tree than both the American tech tree and German tech trees respectively. Unlike both America and Germany the Ussr developed many different types of break through tanks, (or heavy tanks). These tanks had a massive scale of armor, and some of the biggest cannons on tanks to date. But even though these tanks had all these benefits which made them hard to kill, they had the most problems of any tank to date. For one the tanks were incredibly slow due to the massive amount of armor accountable on the tank. Because of this there were also frequent engine problems due to overweight and engine failures from catching on fire. Second the tanks took a ridiculously long amount of time to reload their main guns because it took so long to load a shell almost bigger in diameter than your head and ridiculously heavy due to the sheer size of the thing. For the top vehicles of the Ussr tech tree there is by far the most variety of vehicles to choose from. There is 2 different types of medium tanks with one being faster and more versatile while the other is a bit slower but more heavily armored and modified. 2 different types of light tanks which both had different reasons for creation (one being for speed and the other for fast reload and maneuverability). One atgm carrier (light armored tanks that carried atgms and could fire them in quick succession). And finally Anti-air vehicles that had not only guns to take care of airborne threats, but even ground to air surface born missiles, (missiles launched from the ground that detonate in close proximity to any airborne target).