The Project 186 armored boats, developed by the Leningrad Design Bureau of the Admiralty Shipyard in 1944, were an improvement on the well-proven Project 161 armored boats. They addressed their main shortcomings: low firepower and limited elevation angles of the 76mm tank guns. Thus, the project included plans to install two 85 mm ZIS-S-53 guns in MK 85 turrets on the boat.

However, by March 1945, when the first ten hulls were in production, the standard turrets had not yet been fully designed. Consequently, it was decided to temporarily install turrets from T-34-85 tanks on the boats, which were later replaced with standard ones. The Project 186 armored boats were built at the end of the Great Patriotic War and managed to participate in combat operations in the Baltic Sea, providing fire support to ground forces. By 1947, about 30 boats of this project had been built, and they remained in service until the 1950s.

The MBK pr.186 (MK 85) was introduced in Update 1.83 "Masters of the Sea". It has powerful artillery and anti-aircraft weapons for a small ship, as well as good protection; however, its speed is low.