As the name implies, this room features the volcano that was visible in the main "lava cavern", prominently in the background. The room itself is a long bridge built directly over lava, with barricades on either side to prevent passengers from falling in. The bridge is surrounded by stalagmites protruding from the lava, and the room is open to the Pyrosphere's extreme heat once again after several indoor rooms.
When Samus visits for the first time, the volcano erupts. It drops up to twelve meteors on the bridge, which Samus will need to SenseMove away from. The floor will always illuminate in the spot where a meteor is about to impact, giving Samus enough time to move away from it. Each meteor spawns a Sova, but she is not required to kill them in order to advance. These meteors are likely launched by Goyagma from the Crater Interior, which is set inside the volcano. They stop after Goyagma is defeated, causing the lava in the crater to drain. The corridor leads directly into a Navigation Booth, the last before the forthcoming boss encounter.
If Samus's energy is low or she is hit by too many meteors, she may die before she reaches the Navigation Booth, where she can restore her energy. She may be able to move faster by rolling across the bridge with her Morph Ball.
After Samus's return to the Pyrosphere, a large portion of the floor in this room has been destroyed and is now exposed to the lava. What caused this is unknown, as the meteors from the volcano did not appear to be strong enough to damage the bridge. The only way to safely pass over the gaps of lava is to Shinespark or, later, Space Jump.
"The Pyrosphere, a simulated volcanic area encompassing Sector 3, was predictably awash in magma flows, lava pools, and a host of beasts adapted to extreme heat. Nonetheless, finding an erupting volcano caught me off-guard, especially when it began raining chunks of flaming rock on me. The Varia feature of my suit quickly became necessary."
- Page 81
- "Sprint up the long walkway as the volcano in the distance spits out Mellas. Watch the glowing spots on the ground to indicate where the Mellas will land and move out of the way, lest they land on you and cause damage. Rush across the walkway and stop in the Navigation Booth across the way to save your progress."
- Page 104
- "Exit the room, stopping to save your progress at the Navigation Booth, and then set out across the long, broken bridge past the next doorway.
- Use Shinespark to leap over the broken parts of the bridge and avoid taking damage from the lava below."