The mecha hydralisk is the ranged attacker for Egon Stetmann in Co-op Missions. They serve as Stetmann's primary anti-air, especially with the Eruditon Missile upgrade, which can deal heavy damage to air units. They can double the damage of their anti-air attacks using the Juiced Up ability. However, this requires energy to use.
Mecha hydralisks can be "recycled" when they die, which will respawn additional mecha hydralisks.
Anti-ground ambusher. Has a spine attack that damages all enemy units in its line of fire. Can use Tunnel of TERROR Algorithm and Focused Strike Algorithm. Can attack ground units. Must burrow to attack.