[DEVBLOG#295] Oxygen and Astrofuel

Hello everyone and welcome to a brand new development blog - and the first one when it comes to covering Vanilla Gravships Expanded at that!

Today, I’m giving you a sneak peek at two huge systems coming to Vanilla Gravships Expanded: the Oxygen Network and the Astrofuel Network. These aren’t just little extras, they’re core to making your gravships feel like actual functioning vessels, and not just floating bases with engines slapped on the side. This is actually something that made me bump this mod in priority: I've seen a picture of a huge base with a set of engines slapped on both sides, moving through the sky on some screenshot. It wasn't a gravship. It didn't look like one.

Of course, this mod will make the system much bigger, much deeper and much more interactive. If you're the kind of player that just wants to slap engines on a flying cube and fly away into the sunset: this mod is likely not for you. If you want to live your space ship fantasies and build an authentic vessel and have it run by an actual crew, check out what we've cooked.

A life-sustaining gas. Used to pressurize rooms, supply breathable air, or fuel specialized equipment and survival gear. Volatile when damaged.

If you’ve ever stepped outside a gravship without a helmet, you know space isn’t exactly breathable. The Oxygen Network makes this a real gameplay factor - no more magically ignoring the fact that your crew is locked in a metal box hurtling through the void.

• Oxygen Supply Lines – You’ll need to connect oxygen-producing modules to tanks, and tanks to vents in habitable areas. No connection = no air.

• Life Support Systems – Oxygen isn’t infinite. Pumps consume it constantly when there's need to repressurize, and combat damage can cause leaks, forcing you to patch things up or watch your crew gasp their last.

• Vacuum Survival Gear – You can now craft an oxygen tank and perform EVA work thanks to it - but if it runs out of oxygen, you will be in terrible danger. Vacuum resistance of all apparel except for the vacsuit has been lowered, meaning your space marines might need oxygen tanks for prolonged operations in space.

A fast-growing aquatic plant cultivated in hydroponics and used to generate oxygen when connected to a life support system. Rots quickly when harvested, making immediate processing essential.

A vital device that processes harvested oxyalgae into breathable oxygen. Converts biomass into gas and pumps it into the oxygen network to supply pressurized rooms and equipment.

This system means you’ll be designing gravships like actual spaceships - carefully planning pipe routes, redundancy, and placement of life support in case things go wrong mid-flight.

A high-energy synthetic fuel. Used to power gravship thrusters and boosters, or to generate electricity in specialized systems. Extremely combustible, it burns violently even in low-oxygen environments.

Forget chemfuel for gravships. That’s planet stuff. Space travel needs astrofuel - a refined, high-energy propellant that burns hot and fast, even in the cold vacuum.

• How You Get It – Astrofuel is made from chemfuel at a refinery or synthesizer. It’s an extra production step, which means you’ll need to manage both resources if you want your ship moving.

• How You Store It – You’ll run astrofuel pipes from tanks to engines, just like oxygen lines. Tanks come in different sizes — from small ones for gravjumpers to colossal fuel bunkers for gravhulks.

• Why It’s Dangerous – Astrofuel is ridiculously combustible. Tanks can go up in massive purple explosions if damaged, and astrofire is nastier than normal fire - harder to put out and twice as deadly. Oh, and it burns in space too.

A specialized structure that refines chemfuel into high-grade astrofuel. It must be connected to the astrofuel pipe network and linked to at least one astrofuel tank to operate. Once connected, it automatically converts inserted chemfuel into astrofuel for use in engines and systems.

The best part? Your gravship engines won’t work at all unless they’re properly connected to an astrofuel network. This means you’ll need to think like a real ship engineer, ensuring every engine is supplied and every tank is protected.

Now, I know what you’re thinking — “This all sounds like extra difficulty.” And you’re right. But here’s the thing: we’re not just making your life harder, we’re hugely expanding what gravships can do.

We’re adding dozens of new structures and systems that will let you create the most varied, unique, and downright ridiculous gravships you can imagine. We’re also introducing real progression - a proper gravship tech tree where every step gives you new tools, upgrades, and ways to customize.

An astrofuel storage tank that supplies fuel for thrusters on a gravship.

For progression to feel rewarding, there need to be problems to solve. The Odyssey DLC, as it stands, doesn’t really give gravships many challenges. Building one is easy, and once you have it, it’s insanely powerful. That’s where we come in - by expanding the systems, we’re creating fault points: missing oxygen, exploding fuel tanks, space management, maintenance demands.

The fun part? As you progress, you’ll fix these faults… or eliminate them entirely. By the late game, you’ll have an incredibly advanced, self-sustaining gravship that laughs in the face of danger - because you’ve earned it.

This is just the start. Over the coming weeks, we’ll be sharing more development blog posts that connect all these pieces, showing you how the oxygen network, astrofuel network, new systems, and the expanded tech tree all fit together into a single, unified gravship experience.

Right now, we’re devoting all our development resources to Vanilla Gravships Expanded. This is our big focus, and honestly, we couldn’t be more excited about it. Every day we work on this mod, it feels like we’re building something that’s going to redefine how gravships play in RimWorld, not just adding features, but turning them into living, breathing, complex machines that you’ll care about, upgrade, and fight to protect. It honestly feels the same as when we worked on Vanilla Psycasts Expanded.

We can’t wait to show you more.

Oh, one more thing. Some time ago, there were worries that we will get rid of uncraftable gravship upgrades and make everything craftable, thus reducing the need to actually travel. I've decided against it. In fact, we already have a list of 6 new uncraftable upgrades that only appear as quest rewards, so there will be plenty to do with your gravship.

And have a little teaser as well: