https://en.wikipedia.org/wiki/IS_tank_family
https://www.globalsecurity.org/military/world/russia/is.htm
I love heavies like this Super T-10M. Equipped with 20mm cuppola turret and a pair of heavy machine guns to deal with prowling enemy infantry.
(https://hosting.photobucket.com/images/j340/ysi_maniac/SuperT-10M.jpeg?width=1920&height=1080&fit=bounds) (https://app.photobucket.com/u/ysi_maniac/a/e58f1c54-aee2-42c9-bc15-f72ec22af374/p/01350f93-0c15-4402-8f87-a2edbd28f66a)
Real world
Constant scale: 1 pix ----> 1 cm
IS-1
IS-2
IS-3
(https://hosting.photobucket.com/images/j340/ysi_maniac/IS_series_1_CS.jpg?width=1920&height=1080&fit=bounds) (https://app.photobucket.com/u/ysi_maniac/a/e58f1c54-aee2-42c9-bc15-f72ec22af374/p/01271f80-f720-48d3-b39b-0a3268883ee3)
IS-4
IS-7
2 T-10M
(https://hosting.photobucket.com/images/j340/ysi_maniac/IS_series_2_CS.jpg?width=1920&height=1080&fit=bounds) (https://app.photobucket.com/u/ysi_maniac/a/e58f1c54-aee2-42c9-bc15-f72ec22af374/p/22acdceb-9c07-4cbd-abfa-0c76c70324e6)
I have not found good sources for IS-5 and IS-6
What if the saga of soviet heavy tanks continued during '60s and '70s?
Here you can see first two members of LB(1) series along with T-10M (RW).
LB-1 armed with a 125mm gun, is here parading in Red Square, Moscow.
LB-2 is armed with a 130mm gun.
(https://hosting.photobucket.com/images/j340/ysi_maniac/LB-1-2(1).jpg?width=1920&height=1080&fit=bounds) (https://app.photobucket.com/u/ysi_maniac/a/e58f1c54-aee2-42c9-bc15-f72ec22af374/p/ecc05358-66da-4a85-93dd-7047e8f5fce2)
(1) LB: Leonid Brezhnev https://en.wikipedia.org/wiki/Leonid_Brezhnev
That bottom one's a neat looking vehicle