The EMP is a special weapon in Fear Effect 2: Retro Helix.
The EMP fires electromagnetic pulses (EMP) that temporarily disable electronic devices. This means that it does not consume ammo, but at the same time does not affect human opponents. The EMP needs the trigger held for several seconds in order to build its charge to maximum before behing fired. The stunning effect on mechanical enemies is only temporary, as such foes that are hit with the EMP need to be finished off with another weapon afterward or bypassed while stunned.
The EMP is best used in the Aqueducts against Fixer enemies or the Cat Eyes of Wing Chune Tower when a quick escape to another area is possible. It is the best means of offense against the M.A.W., where a quick escape is necessary.