The impact hammer has two firing modes. Pressing the secondary trigger will result in a quick but weak pulse capable, if timed perfectly, of reducing the damage caused by an incoming rocket. Holding down the primary trigger builds pressure in the piston. At maximum pressure the impact hammer is capable of inflicting over 100 hit points of damage, instantly fragging somebody at full heath and no armor. It is common practice to use the dodge mechanism to propel yourself into an enemy while using the impact hammer.
Players can also use the hammer to propel themselves into the air much higher than the player would normally able to jump. Simply charge the hammer, aim at the floor and jump immediately after letting go of the charge. This is very similar to Rocket Jumping.