I’m not planning to implement it, at least for the next couple of years, so I want to post it here to save the idea for the future or for someone else. The idea itself is entirely mine, although I used an LLM to help organize it and prepare this post.
Main idea
The planet has two types of areas:
- Safe zones – where the player can build permanent factories and train depots.
- Danger zones – trains cannot stay there for a long time.
Time is important: a train must reach its destination, complete its task, and return to a safe zone before it is destroyed. This also prevents the player from simply parking a train at every resource point — expedition trains need to wait in safe areas and travel out when needed.
Planet environment
One possible environment could be a planet covered by a dangerous gas. Trains and other equipment can operate outside safe zones, but only for a limited time before they take too much damage.
Resource platforms could occasionally rise from underground at known locations. These platforms contain valuable resources, but are also occupied by enemies. When a platform appears, the player needs to send one or several trains to it. The trains must fight the enemies, collect the resources, and return to a safe zone before taking too much damage.
This could require different train designs or several specialized trains working together: for example, a combat train to clear the platform and another train with drones to collect the resources. The collected resource could also spoil over time, making the return trip an important part of the expedition.
The resources collected during these expeditions would be required to produce the planet’s new science pack. Other resources could be imported from other planets, similar to Aquilo.
Trains
The Modular Trains mod could be used as a dependency and as the base for designing expedition trains. Building the right train for a specific expedition should be one of the main challenges of the planet. There are also existing mods that add turret wagons, radar wagons and other specialized train equipment. These ideas fit the concept well and could be used as a base, although they would probably need to be reworked and balanced for this planet.
The goal is to have different possible train designs: combat, scouting, resource collection, or trains that combine several roles.
More distant areas could require different or more advanced train designs, so increasing resource production also means improving the expedition trains.
Rail network
Building rails should also be an important decision.
Rails in the danger zone could require Advanced Foundation, so early on the player must carefully choose where to build the main railway lines. Advanced Foundation has to be produced elsewhere and delivered by rockets, which limits how quickly the railway network can expand.
Later, after its production and delivery are automated, expanding the network becomes much easier. The player can build more lines and reach more distant areas with more difficult expeditions and larger resource rewards.
Additional details
- Limited radar range. The planet could have very limited visibility, making radar trains useful for exploration and expeditions.
- Artillery requires vision. Artillery could stay in the safe zone, but it cannot find targets by itself. A radar train would need to enter the danger zone and provide vision before artillery can attack.
- Rail damage. Plasma storms or other environmental effects could sometimes damage rails in the danger zone. This would create a use for automated repair trains.
- Small safe islands. Small safe islands could exist inside the danger zone and be used as train depots. Their limited size would allow only one or two trains to stay there and would also limit the maximum practical train length. This could make them useful as intermediate bases without allowing the player to build a full-size depot or factory there.
- Expanding the safe zone. It could be possible to expand the initial safe area, but expansion should require something valuable instead of being easy and unlimited. One idea is to get the required material by destroying resource platforms, creating a choice between keeping a platform for resources or destroying it to expand the safe area.
- Known platform locations. Locations where resource platforms can appear could be known in advance. This allows the player to build stations and circuit logic there, and later automate sending expedition trains when a platform appears.
UPD: - Minimal stationary factory. The stationary factory on the planet should be intentionally simple. Its main purpose could be converting the spoiling resource brought back by expedition trains into a stable resource. Around 80% of the planet’s gameplay should happen around trains: designing them, preparing expeditions, building the rail network, combat, collecting resources and bringing them back safely.
The idea is completely free to use.