Terrain
The terrain on a map affects unit movement, vision, and the defense attribute of units stationed in the terrain. The different types of terrain include: Roads, Plains, Woods, Bases, HQs, Ports, Cities, Airports, the Sea, Reefs, Shoals, Rivers and Mountains. Weather conditions can also affect vision and movement of ground units. Fog of war may also be enabled, whereby a player's vision depends on the individual units' lines of sight, which varies from unit to unit.
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