Suppressive Fire is a special kind of attack action that is available when using automatic weapons. As a full round attack, make a single attack roll at a square within your line of sight and the weapon's maximum range (range increment penalties apply). Until the start of your next turn, anyone who is within or passes through a line between you and the target square must make a will save with a DC of your attack roll. If they pass, they are unaffected and may continue to act normally. If they fail, they immediately go prone and become entangled until the start of your next turn.
Performing Suppressive Fire requires and uses ammunition equal to 5 automatic fire attacks (usually 10 rounds). Until the start of your next turn you take a -2 circumstance penalty to your armour. Suppressive fire is a fear effect.