Warcraft II is a real-time strategy game. In Warcraft II one side represents the human inhabitants of Lordaeron and allied races, and the other controls the invading orcs and their allied races. Each side tries to destroy the other by collecting resources and creating an army. The game is played in a medieval setting with fantasy elements, where both sides have melee, ranged, naval and aerial units, and spellcasters.
Warcraft II requires players to collect resources, and to produce buildings and units in order to defeat an opponent in combat. The Human Town Hall and Orc Great Hall produce basic workers that dig gold from mines and chop wood from forests and then deliver them to their Halls. Both buildings can be upgraded twice, each increasing usable resources per load from the workers. Players can also construct Shipyards, which can produce both combat ships and Oil Tankers. Tankers build construction offshore Oil Platforms and then deliver the oil to buildings on the shoreline. As all three resources are non-renewable, players must use them efficiently. Forests can also serve as defensive walls in the early game when combat forces are small.
Workers can also construct Farms, each of which provides food for up to four units, and additional units cannot be produced until enough Farms are built. Farms, being very tough for their cost, are also employed as defensive walls.
Humans and Orcs have sets of buildings with similar functions, but different names and graphics, for producing ground, naval, and air units. All but basic combat units require the assistance of other buildings, or must be produced at buildings that have prerequisite buildings, or both. Many buildings can upgrade combat units. When advanced units appear, the Orcs have a strong advantage in ground combat, while the Humans have the more powerful fleet and spellcasters. The most advanced ground combatants on each side can be upgraded and taught some spells, which are different for the two sides. Some campaign missions feature hero units, which are more powerful than normal units of the same type, have unique pictures and names, and must not die, as that causes the failure of the mission.