The Security Robot B.O.X.[1] (ボクス Bokusu?)[2] or B.O.X. Robot[3], commonly referred to simply as the Security Robot by Adam, is both the fifth and the ninth boss Samus faced aboard the Biologic Space Laboratories research station in Metroid Fusion.


B.O.X. was a six-legged, spider-like Security Robot designed to protect the BSL Research Station from the captured alien bioforms found within the station's sectors. Though it was a machine, the organic components in B.O.X.'s neural network were still vulnerable to an X Parasite infection, eventually rendering it yet another tool at the disposal of the X. This infection took place after Samus Aran's first encounter with it, which exposed its organic components.


Sector 3 (PYR)[]

Samus first encountered the Security Robot B.O.X. in Sector 3. After downloading the Super Missile data, Samus discovered that her way back was blocked by a destroyed hatch; the floor near the hatch had also been ruptured recently. Following the rumbling noises coming from overhead led her back towards the Data Room, which B.O.X. was busy destroying.

In battle, B.O.X. attempted to ram into Samus and also periodically fired grenades that would launch two pillars of fire when they exploded. These pillars alternated between short and tall and moved sideways at a steady rate. However, they could easily be avoided if Samus positions herself above the grenade just before it explodes, as the pillars cannot reach that high above the detonation point. In order to dodge the brunt of its attacks, Samus was forced to hang from the Ladders above B.O.X.; this lofty position enabled her to easily fire her newly acquired Super Missiles into the robot's core, slowly breaking through to B.O.X.'s neural network.

Once its neural net was revealed, B.O.X. broke off its attack and escaped through the roof, giving Samus a way back to the Navigation Room. It can be safely said that this breach in B.O.X.'s armor permitted the X to infect it.

Sector 6 (NOC)[]

Later on, B.O.X. was positively identified as an X host. Samus' computer told her that the "organic components that form its neural network" had been infected by the X; Adam ordered her to track it down from where it had last been seen, Sector 6, and terminate it.

Attempting to enter a restricted area, Samus set off an alarm, alerting B.O.X. to her presence. As she tried to retrace her steps, Samus encountered B.O.X. in a room she had previously passed through. It was similar in layout to the room where they fought in Sector 3 -- Samus could bomb the ceiling to reveal monkey bars from which to hang. In this room, however, the floor was covered by a shallow pool of water which had been electrified by the exposed parts of B.O.X.'s machinery, electrocuting Samus whenever she fell in.

The B.O.X.'s strategy had not changed much, but it had replaced its pyrotechnic bombs with seeker missiles, which it periodically fired in groups of four. Due to the cramped conditions, B.O.X. could also jump high enough to hit Samus while she was on the ceiling, forcing her to exercise caution when aiming for its core. However, if she hung on the very edge of the monkey bars, the B.O.X could not jump far enough to hit her.

When Samus destroyed the core, the B.O.X. Robot's infected neural network flew out and transformed into a Core-X capable of shooting beams. By defeating and absorbing this Core-X, Samus restored her Wave Beam.


In the prototype builds, the bombs dispatched could be destroyed by missiles or a Charge Beam shot.

  • Why the B.O.X. destroyed the Data Room in Sector 3 when it had not yet become an X-host is unknown. It could have simply gone rogue, and destroying the room may have been a result of a program malfunction. It may have also possibly been attempting to prevent what it perceived as a threat, Samus, to become more powerful; this would however imply that it had confused the SA-X and Samus to be the same individual, or that it was operating under the instructions of the Galactic Federation conspiracy, which is unlikely because Adam had told Samus to go to that Data Room and download the Super Missiles. Also, it may very well be possible that the B.O.X. may have ascertained that the X could download data as well, and it was destroying another Data Room to prevent them from doing so.
  • Because B.O.X. is fought twice, VS. BOX is the only unique boss theme that is heard multiple times in Fusion. All other boss themes are either shared between multiple bosses (such as VS. Ishtar, Gedo) or only heard once (such as VS. Marukara).
  • Worthy of note is the fact that the brain resembles a miniature Aurora Unit, suggesting that they can be installed into portable weapons platforms. However, the brain actually bears more resemblance to the MB's first form featured in Metroid: Other M.
  • B.O.X. is one of the few bosses that does not have a Gadora guarding it, even after it becomes an X-based boss. This is justified by the rooms it is fought in being passed through prior to each fight.
  • On Easy mode in the Japanese version of the game, B.O.X. has half health and takes longer to use its weapons.
  • In an earlier prototype build of Metroid Fusion, the bombs produced during the first fight with the B.O.X. Security Robot can be destroyed with Missiles or a Charged Beam shot. This is no longer possible in the final build (in which the bomb deflects or ignores most weapons fire, becoming immune to them).
  • It is unknown if there was more than one Security Robot on board the BSL Station. However, the number '5' is printed on B.O.X.'s front legs, suggesting that the unit Samus encounters is one of a series.
    • However, assuming that B.O.X. is part of a series, it is entirely possible that the Security Robot was not designed specifically for the B.S.L. Station, and that Security Robot units 1-4 (and possibly 6 and up) are located on different Galactic Federation installations, respectively.
  • When hit with a Diffusion Missile in Sector 6, it seems to slow down, allowing Samus to land a few more hits. This may, however, just be the game's framerate slowing, giving more reaction time to the player.
  • The leftmost part of the monkey bars represents a safe spot from the B.O.X's jump attacks. In the second fight, the rightmost part works too, and the B.O.X.'s missiles can be dispatched easily with the Plasma Beam.
  • A screenshot of Samus battling the B.O.X. Robot apears on the Nintendo Monopoly board.



  1. ^ "Security Robot B.O.X. detected in Sector 6 (NOC). Engage." - Metroid Fusion Map Objective
  2. ^ Metroid Prime & Fusion Original Soundtracks
  3. ^ "B.O.X. Robot destroyed. Leave Sector 6 immediately." - Metroid Fusion Map Objective