Before the introduction of the M-560 Hydra, missile launchers either focused on bringing down a single armored target or simultaneously neutralizing multiple unarmored opponents. With the Hydra, a soldier no longer needs to choose between the two.
The Hydra releases a barrage of miniature missiles, each guided by an independent homing system that seeks out exposed enemies. On impact, three shaped charges per missile explode in sequence. The first overloads the target's kinetic barriers before the second destroys its armor, clearing a path for the third warhead to detonate inside the target.
Single-player: The Hydra missile launcher can be found during Tuchanka: Bomb while defending Lieutenant Victus, between the pillars to the right of his position. It can also be found during Priority: Thessia, before you encounter the first Banshee in the mission, and again towards the end of the mission during the final run to the temple. The Hydra is found again during Despoina: Leviathan, where it can be found next to the crashed Kodiak. The Hydra makes a final appearance during Priority: Earth where it can be found in the area containing the Thanix missiles, in one of the shophouses under the counter. Two more can be found in Omega: Aria T'Loak (Mass Effect 3), in the section with the Rampart Mechs and the lone Atlas.
The Hydra, like the Reaper Blackstar and the M-920 Cain, must be charged before the weapon fires, but unlike the Cain and Blackstar, the player can hold their charge for as long as necessary and release when they are ready to fire. Being hit while doing this does not break the charge.
The weapon is incredibly useful in many ways in the final mission, particularly when facing a horde of Brutes, as its devastating payload of heat seeking missiles can kill up to four of them at once. It is also useful for taking down the Harvester that appears or taking out the Banshees that appear near the end of the fight.
It is not advised to fire the weapon with an enemy up close if you want to clear the area. Since all the missiles will concentrate on that one enemy, it is best to hold your charge until you have a clear shot of as many enemies as possible.
The Hydra will not cause any splash damage to Shepard or any squadmates.
On higher difficulties, if a player intends to quickly kill a hardened target such as the Atlas during the Tuchanka: Bomb mission, it is better to first kill any nearby enemies since some of the missiles may seek out these enemies, thus meaning fewer missiles will seek out and hit the intended target.
The Hydra shoots eight missiles when it is fired.
If the player picks up a new weapon while holding this, the weapon will be holstered on their back and unusable.