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This article is about the Bulb Zone. You may be looking for the Bulb Zone Caves.


Detecting volcanic activity, and several unusual electromagnetic signatures in the region. Exercise caution when diving deeper.

― PDA, Dialogue


The Bulb Zone is a unique biome bordering the Northeastern Mushroom Forest, the Crash Zone, the Mountains, and the Crater Edge.


The Bulb Zone is characterized by small crevices and overhangs in a vast, sandy dune-like area. It is also abundant with small brown algae, and a large variety of plants with blueish-purple hues, the most notable of which being the various sized Bulb Bushes. A deep blue hue shrouds the biome which may make hazards difficult to spot.

The Bulb Zone is deep and home to certain dangerous fauna. Notable predators, such as Bonesharks and Ampeels, can be found scattered throughout the Bulb Zone. Occasionally, Mesmers can also be found.

Pods of Reefback Leviathans can be found above the Bulb Zone.

Due to its proximity to the Crash Zone, the southern half of the Bulb Zone is subject to Radiation. If the player has not repaired the Aurora's drive core, a Radiation Suit is strongly advised to explore the southern region.

There is a cave system located below the Bulb Zone, known as the Bulb Zone Caves. These caves are accessible via any of the three entrances located within the biome. One of the caves links to the Mushroom Forest Caves. Rubies can occasionally be found in the caves.

Several Lava Geysers can be found in this biome. This, together with the Bulb Zone Caves, suggests a small amount of volcanic activity. According to the PDA Dialogue, there are strange electrical signatures in the Bulb Zone, which likely originate from Ampeels.

Two large Wrecks are located within the Bulb Zone, containing several fragments.

Two Sea Crowns can be found here.

A single Supply Crate is found along the Crash Zone border. The only other ones are found in the two wrecks. 

Spoiler alert: The following section contains story related material.

An Alien Arch Cache is found in the Bulb Zone, linking to the Primary Containment Facility.

An entrance to the Lost River is found on the Bulb Zone's border with the Mountains.



  • The Bulb Zone was originally named the Koosh Zone, but it was renamed to prevent potential copyright infringements.[1]
  • In early versions of the game, the ambience for this biome on the surface contained a strange horn that could be heard in the distance. This ambience was shared with the unused Arctic biome. It is likely these were placeholders for these biomes.