Seedworld (hypothetical game concept)

Space Stage

After completing the Civilization stage and uniting all the cities on your planet, you've already seen everything your planet has to offer at this point and the only place left to go is up... and I'm talking ALL the way up, right into the stratosphere! that's right, it's time to take one small step and a giant leap for creaturekind as you, the captain, must leave the safety of your homeworld behind to explore the stars to expand your civilization into a spacefaring empire as you colonize planets (colonies can be built on either terrestrial planets or gas giants, colonies built on gas giants will take the form of floating cities kinda like cloud city from star wars), befriend and/or battle other alien empires (you can also trade, entertain, or do recreational activities such as spaceship races with them), encounter cosmic phenomena such as black holes and protoplanetary disks (black holes can act as shortcuts to different corners of your galaxy if your ship is equipped with a wormhole key) members of allied empires can carry out orders on your captain's behalf, but only after you build up a specific amount of trust after allying with them. if you decide to be a jerk for some reason and destroy one of your allies ships (or blow up their homeworld with a planet buster) for the fun of it, the trust level you worked so hard to build up will go down and before you know it your allies will suddenly become your enemies. your actions have consequences.

When you first enter this stage is to design a spaceship for your captain to begin your journey into space, at first your ship will only be able to travel to other planets in your home star system. after your first mission, which is to establish colonies on all the neighboring planets in your home system, you will unlock the Interstellar warp drive which will grant the ability to freely traverse outside your home star system and traverse your own galaxy exploring the cosmos at your own leisure. however you are unable to leave your own galaxy (until the next stage little foreshadowing right there) after that you can now build two additional spaceship classes outside the captain's ship: fighters which are for patrolling areas of space occupied by your empire and defend it from any hostile alien invaders, while shuttles are for transporting passengers and cargo across the cosmos. other editors unlocked in this stage include ones to build satellites for establishing interstellar communication, space probes to send down to collect information from unexplored planets, robots to help assist with manual labor and other day-to-day tasks, and space stations to act as a home for your astronauts and off-world research base to test out new technology that can't be done on the surface of a planet (such as upgrades to your captain's ship)

The goal of this stage after you're done exploring the galaxy and establishing your interstellar empire (both of which take up a good chunk of the stage) is to discover the truth behind the origins of your species, of which you will find clues to on random inhabited planets you visit in the form of "seeds", metal pods of mysterious origin that seem to be ancient technology more advanced than any other known empire in your galaxy. if these seeds look familiar, then they should: they're the same pod as the one you saw hit your home planet in the opening cutscene before entering the planet creator, the one that turned a lifeless ball of rock into a habitable world teeming with life. someone, or something... has been using these pods to seed planets with life all across the cosmos, "seed worlds" if you will. this trail of clues will lead you to the galactic core, at the very center of your galaxy. once you enter the galactic core you will be hit with a blinding light as a massive, booming voice speaks to you. this is the god of your universe, the one who sent the pod to your planet billions of years ago that is responsible for your species very existence, "The Maker" himself. The Maker reveals himself as an immortal being who came from another galaxy far, far away that has been traveling from galaxy to galaxy populating planets with life wherever he goes. The Maker then as a reward for finding him, something that no other spacefaring civilization has ever successfully managed to do, gives you "the seed" granting the ability to seed lifeless worlds and turn them into habitable ones just as he did to yours and many others, and an intergalactic warp drive that'll allow you to travel outside your home galaxy. he then teleports you back to your home planet where your captain is given a hero's welcome by your civilization, ending the space stage on a happy note. but this is not the end, as we have one more stage left to go...