
Cerys
You discover Cerys, a moon of Fulgora whose ruins lie frozen under a thick layer of dry ice. As you touch down, methane ice crystals scatter into the vacuum. Asteroids wander overhead, along with a gentle solar wind under Fulgora’s magnetic influence.
The moon's play area is finite. Features of the terrain curve as you approach the edge. As dark settles, the day-night boundary travels across the moon's surface.
Many frozen structures lie embedded in the surface. Though made of new materials, they bear the hallmarks of the Fulgorans. As you explore, it becomes apparent that without lightning, they turned to another source of power.

Methane ice, nitrogen-rich minerals, and nuclear scrap can be found on the surface. Defrosted wrecks can be restored to working order by several new mechanics for repairing found structures. Along with the belts, pipes, modules and other starting materials found on the surface, the engineer must jumpstart Cerys back to life.
Eventually, one can rediscover the workings of plutonium, providing new reactors, a Tier 4 radioactive module, and upgraded nuclear weaponry that can blast a hole in the Cerys magnetosphere and allow the safe landing of cargo.

Designed in the two months following the Space Age release, Cerys is designed as a vanilla-friendly add-on of no lower quality than the official planets. Unlike those planets, the design relies on cargo drops of materials being initially restricted.
For compatibility with vanilla, there are zero changes to vanilla items, recipes or features. However, other mods that make modifications to vanilla are not necessarily compatible with Cerys.
We have a vibrant community on our Discord server which originally grew around this mod, you are welcome to join.
Reviews
- "one of the best mods ever made. every recipe has a purpose. does not waste your time." — notnotmelon
- "Cerys is a frankly outstanding example […] each planet should be unique feeling, which is hard as hell to pull off, but when it works, the results speak for themselves." — abigailambidextrous
- "This is honestly my favorite planet mod. I did a run playing all of them recently and this one really stuck with me" — Rhllorme
- "Top, top tier work here. Will add this mod to any future SA run" — OfferAccomplished388
Related Mods
Using the mod Cerys Start you can play Cerys without an existing save.
The mod is now stable enough that we encourage other mods to build on top, and you can find many third-party mods for Cerys on the portal. If you're looking for a challenge, there is a first-party mod Hard Cerys.
Cerys itself has Flare Stack as a dependency. At launch, Cerys contained its own port of Flare Stack to 2.0. We later assisted snouz to port the original mod. As a result, with Cerys installed, the Flare stack is moved to the Cerys tech tree and the Incinerator is disabled.
Localization
Cerys is available in the following languages: English, Chinese, French, Ukrainian, Korean, Russian, Japanese, German, Brazilian Portuguese.
To update the translations or translate more languages, you can submit a pull request on Github (after playing the game to get context.) Please note that some locale lines are stored in the PlanetsLib Github.
Credits
Gameplay, code and design by thesixthroc. Art and creative collaboration by Tserup.
Special thanks:
- Creators of open-source assets used in the mod as detailed in the Credits file, especially the musician Scott Buckley.
- snouz for the teleporter graphics and other graphical polish.
- thelordthygod, bunshaman, noodlebox, Quezler, notnotmelon, Samario, Nuker299 and degasus for technical contributions.
- Schlumpf, Astorin, Betanona, cyx2015s, Houraiji-Kyuusyou, Fr-Dae, click0, GafarovMaxim and duhyukora for translations.
- Baroque Tier, Samario, NekoBaron, rjdunlap, xbarsigma, Preceti, notnotmelon, LunarNex, Ellthan, Tetlanesh, Sapheroni, Volodath, Fallen, Citizen Joe, Another Zach, Frontrider, Loup&Snoop, sourcerator, Ellthan, hgwaz, Tsumiki Miniwa, lachtan, boomshroom, Magix39, xor50, Golinth and many others for valuable feedback.