- Sector 5 (ARC)
Gravity manipulation bioweapon developed by former Federation scientists. This fearsome creature possesses a gravity unit that can increase the gravitational field by 10 times within a 100 meter radius. The field is powerful enough to overcome the thrust of normal missile and rocket attacks, causing them to drop to the earth in mid-flight; when the drive is active, Nightmare can only be damaged with beam weapons. Nightmare is equipped with a powerful battery of antipersonnel lasers and its biological component is heavily shielded. Once the face shield is destroyed, a grotesque green face with six jaundiced eyes is revealed. The shield not only protects Nightmare from damage, but also shields the face from the outside air. Without that shielding, Nightmare will slowly decompose. Though powerful and intelligent, Nightmare is single-minded and lacks advanced cognitive skills required for higher-order tactics, so must be outsmarted through speed and cunning rather than brute force.
Nightmare can first be seen flying in the background of Sector 4 once the cooling system has been destroyed. After it was infested by the X, Nightmare went on a rampage, destroying large swaths of Sector 5 before settling in an equipment dump in the lower reaches of the area.
Nightmare is one of the most difficult bosses in the game. Nightmare is fought in three phases.
PHASE ONE: Nightmare flies at the same height as Samus and shoots 6 lasers out of its arms. Space Jump to the upper-left corner by the broken door to lure him to the top of the screen, then Space Jump beneath him and hit the gravity unit with a Charge Beam. Two shots will reach the next phase.
PHASE TWO: The gravity unit activates, making Samus fall slower and hinders jumping. He will also fire lasers from his arms. If you kept him at the top of the screen, all you have to do is stand beneath him and jump and fire Charge Beams at him. After six shots, the gravity unit will flash and slime will dribble out of Nightmare’s mask. Missiles and any other object will be sucked towards the gravity unit.
PHASE THREE: The hardest part. Nightmare will fly towards you slowly, firing a steady volley of lasers from his arms. If you jump on the ladder, you can pummel him in the face with Super Missiles or the Charge Beam while he flies towards you. When Nightmare is roughly one or two tiles away from Samus, watch his volleys and drop to the ground beneath him, Morph Ball, and roll under him. Proceed to Space Jump around him, taking a few shots at his face when he flies towards you, then dropping down and Space Jumping back up behind. After several seconds, he will resume flying slowly at Samus. Jump back on the ladder and repeat.
Defeat the Type A Core-X to gain the Gravity Suit.
In Metroid: Other M, it was revealed that Nightmare was originally developed by the Bottle Ship scientists. After Melissa has been defeated, Samus will retrace her steps through the Bottle Ship in search of Adam’s helmet. When you return to Nightmare’s room, you will notice his corpse is missing, removed to the B.S.L Station for reconstruction.