Scorpions have a unique primary firing weapon. By pressing and holding down the primary fire button it increases the gauge that shows how big, or small the ammunition will be. The ammunition that comes out is a green strand that goes through the air horizontally until it snags something. When it eventually snags an object, vehicle, or person it then wraps around that thing and clings until it eventually 'pops', thus inflicting damage.
A Scorpions secondary fire are two long blades that protrude from the sides and stay extended for as long as you hold down the secondary fire button. Be careful with these blades, because they will break if you hit them off of a wall or some other inanimate object. To protect them from this simply release the secondary fire button and let them come back to the Scorpion's side.