Lurkers are equipped with the TMD Shield and Cloak power. Shield protects the soldier, and damages anyone trying to attack it with melee. Stand in place to cloak, and become nearly invisible.
The Lurker has a Shield that bounces damage back at the cost of E99 energy. If you stand in place and don't move or shoot, you will become invisible. When you turn invisible, you use less E99 Energy.
This unique multiplayer perk allows the Lurkers shield to reflect more melee damage than normal.