Quadraxis

Quadraxis was a huge security drone created by the Luminoth to protect the Sanctuary Fortress. However, the Ing conquered the fortress, and posessed Quadraxis, taking him to guard the Ing Hive instead. After Samus Aran landed on Aether and restored power to Torvus Bog and the Agon Wastes, she went to the Sanctuary Fortress to restore power to it as well. In turn she entered the Ing Hive and defeated Quadraxis.

Battle
Quadraxis, in its first form, uses anti-matter lasers, missiles, and a tornado attack similar to the one used by the Quad Robots also found in that sector. The only difference is that while the Quads spin around the arena trying to come in contact with you, Quadraxis will stay in the middle of the arena, attempting to suck you into it. There are multiple ways to dodge this attack. One way to avoid this attack is to get on the far edges of the arena when it begins to start this attack. Another is to shoot its feet with a charge beam or screw attack into it. Quadraxis is damaged by hurting its knee joints with missiles and its foot weaponry with the Boost Ball or Morph Ball Bombs. Once its main body is crippled its head will detach and fight on its own. The head will use a shielding device which receives energy from the body. Using the Echo Visor, Samus must destroy the shield transmitter on the body and attack the receivers on the head. Once one receiver is destroyed, Quadraxis will try to re-establish the lost link, and summon Dark Quad MB and CM robots in the process. The best way to deal with these is to take the heads off and keep moving so the Quad cannot spin into Samus, because if she takes the time to completely destroy the quad(s), Quadraxis will re-establish the link. Once all the receivers are destroyed, Quadraxis's final form will engage. Quadraxis's final form is defeated by using the legs as ramps, use Boost Ball to boost onto one of the two Bomb Slots on its body, and drop a bomb. Once bombs are dropped in both, Quadraxis will die, leaving Samus the Annihilator Beam. Once she returns to U-Mos, he will give her the Light Suit, which will allow her to travel on a Light Shaft to the portal that will transport her to the Sky Temple Grounds.

Logbook Entry

 * Quadraxis: The Quadraxis went rogue and entered the service of the Ing. Its primary weapon system fires destructive matter-antimatter blasts. It uses a powerful missile battery for long-distance attacks. The Quadraxis is incredibly durable and well-armored, but its leg and foot joints are vulnerable. Damaging these joints will eventually render it immobile.


 * Damaged Quadraxis: Though the main body is disabled, the tactical control unit within it is still active. It will guide the Head Module in battle via high-sonic transmissions. Disabling this module will impair the Head Module’s ability to fight.


 * Shielded Head Module: The Head Module of Quadraxis is highly mobile and well armed. It is shielded by an impervious force field. Tactical commands are sent to the module from the crippled main body: sever this link to impair the Head Module’s combat ability.


 * Stunned Head Module: Head Module is unable to receive tactical data. Force field offline. Unit is generating drones to defend itself while it attempts to restore tactical link to main body. Destroy sonic receptors on unit to prevent this.


 * Final Head Module: Module has lost its tactical link to the main body. Two points of structural weaknesses have been located on its hull: Morph Ball Bombs can cause damage to these areas. Scans indicate that the Spider Ball can attach to the Module’s outer hull.

Trivia

 * Disassembled parts of Quadraxis can be seen scattered throughout the Fortress Temple entrance, suggesting that the Luminoth were in the process of making more than one.
 * This could also suggest that the parts were already on Dark Aether when it formed, and the Ing somehow managed to properly assemble it; the parts lying about on Light Aether could suggest that the Luminoth didn't manage to finish Quadraxis before their defeat.
 * Quadraxis is arguably the largest boss in the Metroid series. Kraid may come a close second.  Kraid may or may not be taller but Quadraxis is definitely wider and would most likely be heavier as well.
 * Quadraxis' head when exposed is similar to an Aurora Unit. This may suggest that it is a Luminoth variant of the Mother Brain created by the Chozo, and the Galactic Federation-created Aurora Unit.
 * In early screenshots, Quadraxis was blue with green armor. Another notable fact is that even though he briefly changes color when possessed at the beginning of the battle, he is the only possessed creature in the entire game to maintain its original color scheme.
 * Probably because of the Ing controlling it, Quadraxis is most vulnerable to the Light Beam.
 * This is the music heard when battling Quadraxis:.