Terrain is categorised as difficult where it will typically slow down any unit moving through it and may cause a unit to become stuck or even fall prone.
Examples of difficult terrain include bogs, swamps, muddy beaches, muddy river banks, deep snow and sand dunes.
When setting up the table for a game, both players should confirm with each other which terrain is considered to be difficult and it should be clealry distinguishable on the table from normal terrain.
Foot-Units in Difficult Terrain
Difficult terrain halves the distance moved by a foot-unit.
Example: Unit A with an SP of 6 runs 2" and then enters a boggy trench, difficult terrain, that is 2" wide. That costs him 4" to get through, leaving him with 6" on the other side.
Mechs in Difficult Terrain
Vehicles in Difficult Terrain
Difficult terrain does not modify the distance moved by a vehicle.
Make a control test (see Vehicles) at the point where the unit enters the difficult terrain, with a -2 penalty if the vehicle is rushing or a -4 penalty if the vehicle is flat-out.
If the test is passed the vehicle continues through the difficult terrain unaffected.
If the test is failed, roll a D6.
Any vehicle starting a move from in difficult terrain runs the risk of becoming stuck and not being able to move that turn. Test the unit's ST before moving it. If the test is failed, the unit is stuck and may not move that turn. If the test is passed, the unit may move as normal.