Tanks of USSR
Soviet tanks tend to be very diverse, without a major defining trait like the soft stats of America tanks or the autoloaders of French tanks permeating them all when they come into their own at high Tiers, but in large part, they trade in something to be able to fit a large gun on a minimally sized chassis. Their heavies tend to be characterized by poor gun handling and mediocre DPM, but compensate for it with tough armor that's heavily sloped to make up for reduced thickness, and almost medium-esque mobility. There are some exceptions, such as the KV-4, with a comparatively sniper-like gun and thick, but flat armor, playing as a stereotypical "Fascist Box Tank" that slowly rolls down a flank and crushes it, but those are the exception. On the other hand, their mediums are very different, nimble and agile multitaskers that can fluently transition between scouting, flanking, and support firing with ease, with hard turrets, excellent sustained firepower, great camo, and pin point gun handling across the board. These upsides come with their own downsides though, which include lower penetration values, generally feeble hull armor, and poor gun depression, which are manageable with proper play, and tend to carry over to the lights. Finally, their tank destroyers provide solid support fire power. They have, all around, great camo, workable mobility, and brutal firepower, at the cost of soft stats and armor on some; these characteristics make them ideal for ambush or sniping gameplay. Overall, they truly come into their own in many ways.
Soviet light tanks are typically the fastest in the game and, like most Soviet tanks, have a small frontal profile and sloped armor.
Soviet medium tanks are also fast and maneuverable, and equipped with accurate guns unlike the other lines in Russian tree (and gets even better in high tier). All are jacks of all trades and very versatile. Unfortunately, most suffer from poor gun depression, limiting their ability to go hull down and makes use of their strong frontal turret.
Soviet heavy tanks have good guns, are fast, and have strong armor; their frontal armor thickness and slope makes them quite difficult to penetrate from the front. There are two lines: the KV line which offers thicker armour and standoff potential at the cost of mobility and the IS line which has armour more reliant on angles, but better agility and alpha damage for brawling.
Soviet tank destroyers have bad armor but they have best camouflage values in game. They offer increased speed, agility, and brute firepower. There are two lines: the Object 268 line which favours alpha damage and the Object 263 line which favours mobility and Damage per Minute.
Soviet self propelled guns are generally quite accurate but don't do much damage. However, they also generally fire their shells in a very high arc, making their flight time long, but able to hit tanks hiding behind rocks and small buildings. They also tend to have higher firing rates than their foreign counterparts.
