Heavy Weapons
(Rule)Description: If an infantry unit moves then it cannot shoot heavy weapons - they either move or shoot, but not both (remember that even if the model armed with the heavy weapon doesn't move, it still can't fire if other members of its unit move). Infantry units that fire heavy weapons in the Shooting phase may not charge into close combat in the Assault phase, although some rare units may be an exception to this.
Note: vehicles, monstrous creatures, riders on bikes (including jetbikes) and certain other models are capable of moving and firing freely with heavy weapons.