Brimstonia Asteroid guide: the moonlet no cluster places
AsteroidsMedium
What the Brimstonia world file generates in the current game, with two in-game examples.
The Brimstonia Asteroid is a 64 × 96 cell moonlet of hot marsh over a small magma core. The game's description promises an abundant supply of sulfur, but the current world file places none: neither sample world held a single tonne of Sulfur. What it does hold is a steam vent, a natural gas vent and a slime biome.
No cluster in the current game places this asteroid, so typing a seed never produces it. Players meet it in custom clusters built with cluster-editing mods such as Cluster Generation Manager. The screenshots below come from the game's own world generator: a Terrania Cluster game in which the Marshy Asteroid placement was replaced by this world file, so the cluster coordinate under each picture does not reproduce the asteroid in an unmodded game.
| Fact | Value |
|---|---|
| Size | 64 × 96 cells |
| Where you find it | No stock cluster; custom clusters only. |
| Biomes | Hot marsh at the surface and below, over a small magma core. |
| Guaranteed | A Steam Vent and a Natural Gas Geyser. |
| Peak light and radiation | 80,000 lux of sunlight and 250 rads of cosmic radiation at the surface. |
Strengths
- A Cool Steam Vent averaging 1.4 to 1.6 kg/s: water and heat for an outpost.
- A Natural Gas Geyser for outpost power.
- Gold Amalgam, 115 to 180 tonnes, plus algae, clay and sand.
- Thimble Reed (Thimble Reed), Buddy Buds and Dusk Caps.
Weaknesses
- No sulfur, despite the name.
- About 370 to 400 tonnes of polluted water and 150 tonnes of Slime: slimelung germs.
- Magma close under the marsh: about 1,000 tonnes.
What to target first after landing
- Land with suits and seal the slime biome from the landing site.
- Cap the Steam Vent and cool the steam into water.
- Run a natural gas generator on the vent for outpost power.
- Mine the gold amalgam.
Surviving the asteroid
Treat the marsh air as contaminated. Short visits in suits, or a sealed outpost on the steam vent.
Example 1: world seed from SNDST-C-1234567
A Cool Steam Vent at (23, 30) with 1.6 kg/s and a Natural Gas Geyser at (37, 58).

| Geyser | Cell (x, y) | Average output | Temperature |
|---|---|---|---|
| Cool Steam Vent | 23, 30 | 1.59 kg/s | 110 ºC |
| Natural Gas Geyser | 37, 58 | 109 g/s | 150 ºC |
Example 2: world seed from SNDST-C-2468024
A Cool Steam Vent at (27, 57) with 1.4 kg/s, a Natural Gas Geyser at (48, 34) and 180 tonnes of gold amalgam.

| Geyser | Cell (x, y) | Average output | Temperature |
|---|---|---|---|
| Cool Steam Vent | 27, 57 | 1.37 kg/s | 110 ºC |
| Natural Gas Geyser | 48, 34 | 92 g/s | 150 ºC |
Role in the colony
In a custom cluster, Brimstonia is a water and power outpost built around its two guaranteed vents. Look elsewhere for sulfur: the Flipped start and Liquid Sulfur Geysers carry it.