In this update, the tank was renamed to 
SDT-58 Vlkodav, changing the “57” in its name to “58.” Additionally, its gun was changed from a 122 mm to a 105 mm.
With the release of Update 1.29, the SDT-58 Vlkodav (Czechoslovakia, MT-9, premium, twin-gun mechanic) will be played in Random Battles by developers and Supertesters.
Historical Reference:
In the late 1950s, the Czechoslovak military formulated requirements for a new heavy tank that would be qualitatively different from all previously developed vehicles. The tank was planned to be equipped with powerful armament consisting of two guns, which was expected to significantly increase its rate of fire. To improve firing effectiveness, the design included an optical rangefinder.
Preliminary calculations showed that installing two powerful guns and accommodating their ammunition would overload the suspension system. Additionally, the vehicle would be quite complex to maintain and expensive to produce. The project was canceled before even a prototype could be built.
Within the game’s mechanics, the vehicle is represented as a medium tank.
