This FAQ addresses common sticking points and queries, avoiding solutions to puzzles.

At what point in a playthrough should I visit Cerys?

At any point works, though the rewards are most useful before Aquilo.

Fulgora and Cerys can be done in either other, though knowing how Fulgora works will help in playing Cerys.

I'd like to play Cerys but not on an existing Space Age save.

Use the mod setting "New games start on Cerys" to spawn on Cerys with power armor and enough technologies to simulate having left Nauvis.

I'd like to take a break from Cerys, but can't drop the parts for a silo.

The QoL mod Planet Hopper was created for these cases.

Is Cerys a puzzle game?

Not entirely. It has many puzzle elements on first playthrough, but has some design elements for replayability.

How do you pronounce Cerys?

Cerys is a Welsh name pronounced "Kehr-iss".

Why does Cerys disable Flare Stack incinerators?

When Cerys was first released, it included a port of Flare Stack to 2.0. This port included flare stacks and vent stacks, but not incinerators, as incinerators are newly redundant in Space Age due to the existence of the recycler.

We then assisted snouz to port the original Flare Stack mod to 2.0. It was decided not to remove incinerators in that port.

If you'd like to use incinerators from Flare Stack with Cerys installed, you can re-enable them in the Cerys mod settings.

Why can't I place space platform foundation around Cerys?

Although this would be fun, asteroid collisions with space platform foundation would break some of our gameplay. Note that some older Cerys saves behave differently in this regard.

Why doesn't the Cerysian science pack follow the naming convention of other science packs?

In our view, it follows the naming convention. Unlike other science packs, Cerysian science is the reverse-engineering of ancient technology found on Cerys, rather than research of a specific knowledge subfield.

Is Cerys compatible with the Plutonium Energy mod?

For now, Cerys removes PE recipes from the tech tree that are duplicates of simpler Cerys recipes. We are in discussions with the PE dev about a better compatibility patch in future.

It may be helpful to note a few features of how plutonium processing works in Cerys (not that it is perfect in any way):

• Since Pu-239 is more fissile than Pu-238, Cerys uses it as the primary isotope in reactors.
• Since Pu-238 is more radioactive, Cerys uses it for non-reactor applications needing radioactivity, (Pu-238 gets the 'bright' icon for this reason.)
• Cerys doesn't have 'mixed-oxide fuel cells' separate to other fuel cells with oxide mixtures.
• Breeder reactors are not as separate entity as these arise when the efficiency of the process rises above 1.

Why are there burning animations on an airless moon?

We agree that it is odd you can’t build burner miners whilst you can burn fluids in a flare stack! Simply put, many Factorio animations still need adjusting for an airless environment, and we hope these fixes can be made in future.

My radiative towers didn't spawn over the lithium brine, is this intentional?

Yes.

I’m totally stumped at the start, I need a hint.

Here are two:

• As with scrap on Fulgora, you can recycle nuclear scrap by hand.
• Try removing the stick.

Speedrunning Leaderboard

Conditions: No other game-affecting mods than Cerys; starts when the player ejects from the platform and ends when leaving the moon; default settings except 'Start on Cerys' (feel free to turn the toast off); shared publicly online.

• No players have a recorded speedrun.