Satisfactory developers admit that designing the caves in the Core Values expansion was their biggest challenge – old layouts won't work in them

Coffee Stain is working on Core Values, an expansion for Satisfactory, and the scale of the challenge turns out to be bigger than it first appears. The action moves underground, but simply adding some lights and building the usual factory down there won't work.

New logistics tools will be required to connect buildings. Conveyor belts are still around, but they're far less useful than before. Another problem for the developers is how to make a cave of the perfect size.

The world of Satisfactory is a large sandbox crafted by hand by the Coffee Stain designers. There are several maps to pick from, but none use procedural generation, so nothing changes between playthroughs. Coal, iron, and copper deposits are always in the same places.

That placement is no accident. Level designers make sure starting resources stay within reach as early technologies unlock. Before conveyors and storage containers arrive, players sprint between deposits, fill their inventory with loose rocks, and carry them back to the base to be refined into usable materials. If deposits are too far apart, the ferrying turns into dull routine.

Once mining drills, refining stations, and component assemblers unlock, the space between deposits fills up with a sprawling factory of interconnected machines. The world is largely untouched, so a factory can spread wide, stack tall, or mix both approaches. Space is virtually unlimited.

In Core Values, the rules change, and factories now have to fit inside an enclosed space. Game director Emmet Burke noted that limited space will be a constraint for players, but it's also a constraint for the designers themselves.

We want to be very careful how much space we allow for different players, because you still want to have the cave feeling. You want to have the little tunnels to explore, but you want to make sure there's always enough areas that if people want to unleash their creativity, they have the space to do that, but then you don't want to just give them a big box [where they can] just build whatever they want. Level design was enormous here.

The maps in the base version of Satisfactory took thought too, but the new expansion raises the difficulty. The developers need to predict how players will lay out factories that exploit the cave's resources, and how much space they'll eventually need. According to Burke, the team is constantly testing factory layouts across the entire biome.

That means factoring in the technologies available at different stages of the tech tree, plus the resources and their quantities. The developers then map out different factory styles to see whether they fit in the cave.

Art director Torsten Gunst described the approach as a triangle.

I always see it like a triangle. We have the cave environment and the size and shape, but we also have the amount of factories you need, how expensive the recipes are, and the size of the buildings."

By keeping an eye on those factors and making tweaks where needed, the team ends up with a unique cave shape that can hold an optimised factory that best exploits the resources found inside.

The studio wouldn't say what the new logistics tools are. Producer Julio Mendez did all but confirm that the cramped caves will push players to embrace them over old methods.

I don't want to spoil anything out right, but there will be challenges that come from the specific new environment that we have.

Making caves that are varied and practical demands careful planning. They can't be too small for the factories players need, but they can't be so big that the challenge disappears. Coffee Stain also knows that Satisfactory players are inventive.

People will find recipes that we didn't even think of. We have a vision of how this is going to be balanced and then... We can't test every single combination.

Then there are players who aren't so skilled at optimisation. They can't perfectly tune the flow of resources so that no machine sits starved of materials or stuck unable to unload its output because the conveyor is full. The studio has a simple rule for them.