The Metro Bus is a civilian bus featured in Mercenaries: Playground of Destruction.
The Metro Bus is one of the largest, bulkiest civilian vehicles in the game. Large, with a white and blue paint scheme, it can travel at a maximum speed of 120 kilometers per hour (~ 74 miles per hour), which can be seen in the challenge "Speed."
Carrying a decent amount of passengers, the Metro Bus has a decent amount of protection, but its lack of maneuverability and bulky size makes it an unwise choice for anything but a joyride. The Metro bus can be seen driving around the Russian Mafia's Head Quarters in the Southern and Northern provinces. Because of its carrying capacity, the Metro Bus makes a good troop carrier and can smuggle a squad of soldiers past enemy lines easily, similar to the NK Cargo Truck. The difference is, none of the factions in-game will fire on the bus as long as the civilian disguise is active.
The Metro Bus is based on the North Korean produced Chollima 84. The Chollima 84 was reportedly manufactured by the Pyongyang Trolleybus Works between 1984 and the late 2000s. Not much is known about the public transportation system of North Korea due to the paranoid and closed-off nature of the government, but it is believed that buses like the Chollima 84 only operate in Pyongyang and Chongjin.