The Bhishma TWMP (भीष्म, a character in Indian epic Mahabharata; Object 188S) is an exported T-90 built in Russia and also license-produced in India by the Heavy Vehicles Factory. India purchased 310 T-90S in 2001 as complete assembled or knock-down kits as part of their military modernization program, and a further 330 tanks would be produced locally by the HVF as well since 2006. Most of the features of a standard T-90A (Object 188A1) are identical on the T-90S, as the Russian Army later adopted the latter as the new MBT in 2005. In this case, a domestically developed mine plough by the Defence Research and Development Organisation (DRDO) is installed on the tank as an alternative to Russian mine ploughs.

Introduced in Update "Sons of Attila" as a squadron vehicle, the T-90S is in fact the tank that set the foundation of the T-90A in Russian service. Not only do they share similar protection and identical mobility, it also has a mine plough for ground digging which can sometimes serve as extra protection against oncoming shells. Due to export limits, the ammunition options are fewer than the T-90A and limited to 3BM42 as its only kinetic shell against tanks of its tier. However, in most cases, the mix of ATGM, HE-FS, and APFSDS are more than enough to handle different targets in different scenarios.