The mecha ultralisk is the heavy assault option for Egon Stetmann in Co-op Missions. Much like the regular ultralisk, they deal heavy area damage and have high health and armor. In addition, the ultralisk can burrow charge an enemy, stunning mechanical units when they emerge under them. They can also research the Mecha Mooch Module, allowing them to take life from nearby ally and enemy mechanical units.
Mecha ultralisks can be "recycled" when they die, which will respawn additional ultralisks.