Ridley's room

Ridley's room, also known as Ridley's chamber , is the room where Ridley is battled in his lair.

Metroid
In the original Metroid, Ridley's room is constructed from reddish violet blocks, with a few metallic silver pillars. The ceiling of the room features silver spikes and red orbs, arranged in a manner that resembles the teeth and eyes of a large creature; a similar structure appears in Kraid's room.

The room is behind an ordinary Blue Door. Ridley resides on the raised portion of a platform in the center of the room, floating above a pool of lava. Samus Aran can choose to fight Ridley head-on, or she can jump into the lava (which actually deals less damage than the boss himself) and shoot Ridley from below with the Wave Beam.

Directly behind Ridley is the only Purple Door in the game. Shooting it open with ten missiles will reveal a room with Holtz, fake lava, and an Energy Tank.

Zero Mission
In the remake Metroid: Zero Mission, Ridley's room is found in the same place as the original game, but its design has been notably changed. The room is constructed from sand-purple blocks, with large columns of ancient temple ruins in the background. The room has a much higher ceiling than before, with the creature-like decorations completely absent.

When Samus Aran first enters the boss arena, she finds that it is completely empty. Without interference, she can cross a bridge over lava and enter the next room, which contains the unknown Gravity Suit and an Energy Tank. However, when Samus returns to this room, the doors lock, trapping her inside. Ridley swoops down from above, and as the boss battle begins, the ends of the bridge crumble away, exposing the lava on either side of the chamber much like the original game.

Super Metroid
In Super Metroid, Ridley's chamber has aspects of both the original Metroid room and the later Zero Mission room. It retains the aesthetics of the room from Metroid, including the silver pipes and the creature-like decorations on the ceiling. It also has the greater vertical height of the Zero Mission room, as well as the pillars and ruins in the background. Additionally, several gargoyle-like statues resembling Chozo heads are situated near the top of the room.

When Samus first enters Ridley's chamber, the room appears dark and empty, only for Ridley to emerge from the shadows in the same manner as he did in the Ceres Space Colony. As Ridley roars and the battle begins, the chamber's background fully lights up as an earthquake floods the bottom of the room with superheated lava that will damage even the Gravity Suit. Upon Ridley's death, the chamber shakes again and the lava seeps away.

With Ridley finally killed, Samus can enter the adjacent room to the left. Unfortunately, she discovers that she is too late to rescue the baby, with its broken Metroid capsule left behind. However, like Metroid and Zero Mission, this adjacent room still holds an Energy Tank.

Inhabitants

 * Ridley

Trivia

 * Metroid is the only game where Ridley's room is not guarded by a Gadora.
 * In Super Metroid, Ridley's chamber contains extreme heat, although this should be nullified by the Varia Suit that Samus obtains much earlier in the game in a normal playthrough. This effect is only relevant if the player is performing a Low Percent Run or Reverse Boss Order Run.