Ask Lemmy

TL;DR Something like Kerbal Space Program but with a bigger emphasis on setting up interplanetary logistics and colonies and an eventual win-state.

So, the premise is that you are the overmind for a race of eusocial cephalopods that live on an Enceladus/Europa like icy moon orbiting a gas giant. You've got the beginnings of a space program using the fact that your workers can survive in hard vacuum for a short time so you can build and send rockets up (easy due to the lack of an atmosphere and small gravity well) filled with eggs and plan manoeuvre nodes where an egg will hatch giving you temporary control of the craft for the life of the current worker (you can also hatch an egg on an ad-hoc basis but carefully planning missions is encouraged as, without other life support, the mass of the eggs is the primary payload mass that determines your delta-v).

You start off low on metal to create rockets (probably a starting stockpile + a very slow trickle auto-mined from your home moon to prevent softlocks) but a metal-rich asteroid has recently been captured as a submoon to your home moon. So your initial goal is to use your starting metal to build something capable of reaching this submoon, mining it, and getting back home to give you more metal to create bigger rockets to explore the rest of the starting gas giant moon system.

You can also start setting up experiments on the different moons and in orbit + a communication satellite infrastructure to get the data back home to start working your way through a tech tree giving you access to more components to build rockets from, more experiments to set up to bring in science faster and, in particular, electronic control systems that allow you to automate parts of the launch/manoeuvre process to break your dependency on the egg hatching mechanic (although these would only work in areas of space you've already visited manually to keep that mechanic working for exploration)

At some point, you unlock the ability to set up colonies on different bodies which allow you to automatically mine resources, build rockets in different places and start to use the automation tech to move it autonomously between orbits and ultimately between colonies. Setting up and expanding colonies would require a resource only available on bodies with a thick atmosphere (of which there would be one in your starting gas giant moon system + a standalone planet that's harder to reach at first but doesn't require you to climb out of the gas giant gravity well to help you expand out into the rest of the solar system) in order to make you still have to face the challenges of getting a rocket out of an atmosphere and/or let you play with SSTO space planes etc.

The point of all this would be to ultimately collect and ship enough resources to start putting together components for a big colony ship that would have to be built in sufficiently big colonies on specific types of bodies and then hauled to the edge of the solar system for construction. You'd then be able to send the fully built ship off into interstellar space and "win".

Also, use n-body physics (potentially a restricted form so the planetary orbits are stable and it only applies to your rockets/satellites/stations) to let super-nerds set up ITN style low energy transfer orbits passing through Lagrange points because why the fuck not. It's a fair amount of extra work for a fairly niche use-case but you did say no compromises.