The various types of terrain in TOI have significant impact on game play. Each terrain type is described in detail below, including terrain movement effects, whether the terrain blocks LOS, etc. This list covers both the terrain printed on the map board and the overlay terrain pieces that are placed on top of the board at the beginning of the scenario, as well as the special terrain features that may be implemented by Operations cards such as wire, smoke, mines, etc.
A hex’s terrain type is considered to be covering the entire hex, regardless of where the actual artwork on the board may end.
For example, if a LOS is drawn through an edge area of a woods hex, where no artwork of woods is present, that hex is nevertheless still considered a woods terrain, and LOS would be blocked.
The information on each terrain type should be interpreted in the following way:
- Blocking Terrain: When a terrain is considered blocking terrain, it will block LOS when units are on the same level, or will act as the “closest obstruction” when determining LOS between units on different elevations (see pages 24-25).
- Movement Cost: This is the cost of moving into a hex featuring such terrain. If a unit cannot afford to expend the movement cost, it may not enter the terrain.
- Cover: This is the number of red “cover” defense dice that this terrain provides any units in the hex when attacked.
- Special Rules: Any unique rules that govern hexes with this terrain feature are detailed here.