The ARM Adv. Construction Sub is a level 2 unit capable of building level 3 naval structures and towers as well as the level 1 Shipyard; it has the strongest nanolathe out of all level 2 construction units (second strongest after the Commander). Also, being an underwater unit, it can only be detected by sonar; the enemy can, however, still see the nanolathe particles. Each Adv. Construction Kbot increases the player's energy and metal storage capacity by 50. Its counterpart is the CORE Adv. Construction Sub.