The ISU-152 is an Assault Gun based on the IS heavy tank chassis, mounting the 152mm ML-20S howitzer in a fixed casemate. It entered Soviet service in 1943 and was used for destroying fortifications and armour at long range; the large HE round was devastating against infantry and light structures. In-game it is a tracked vehicle weighing 46 tonnes with a crew of four — driver, gunner, commander, and loader — and a V-2IS diesel producing 520 horsepower for 11.3 hp/t and 35 km/h forward.
The main armament is the 152 mm ML-20S with OF-540 and BR-540B and a 22.58-second reload; the commander has a 12.7mm DSHK for anti-air and local defense. The commander turret is stabilized. The gunner uses a 2x telescope with no rangefinder.
This vehicle features a single addon: 122mm A-19C. The 122mm A-19C addon costs 500 points and replaces the stock 152mm ML-20S with the high-velocity 122mm A-19C cannon. This upgrade completely overhauls the ammunition suite: the BR-540B APHEBC is replaced by the BR-471B, providing an additional 34 mm of maximum penetration (increasing from 171 mm to 205 mm). Conversely, the OF-540 HE shell is replaced by the OF-471, which drops the total explosive mass from 5.86 kg to 3.3 kg, reducing its effectiveness against infantry and light vehicles. However, the reduction in caliber significantly improves the weapon's handling, drastically reducing the reload time from 22.58 seconds to just 18 seconds.
