Avorion
The sci-fi space exploration game Avorion is available on Steam. It has procedurally created galaxies where you can build, fight, mine, and trade. Plus, you can play with other people online, make your own ships out of different materials and guns, and they can be any size you want.
In Avorion, the only things that can stop you are your ideas and creativity. You can look through the game’s Steam Workshop to see and use space station or ship designs that other players have posted if you’re not sure of your own building skills.
Starmade
Starmade is a voxel-based sandbox space game that you can get from Steam or the publisher’s Web site. Piece by piece and block by block, you’ll be able to build ships, space stations, or just about anything else you could want or need.
You can fight AI by yourself and go at your own pace, or you can join a multiplayer server for a more exciting and dangerous PvPvE experience. It costs $15 to buy the game, but sometimes it’s on sale on Steam for only a few dollars.
Space Engineers
Space Engineers is a space exploration and sandbox game with building elements, so it’s a lot like the first two games. However, it has a lot more to give in terms of survival, automation, and engineering uses.
As you play, the physics make things feel more real and engaging. However, try not to get lost in space or have one of your devices break, become unbalanced, or escape your control. The game is on Steam for $20 or less.
Minecraft
Even though Minecraft isn’t really on this list, it still counts because you can make any kind of spaceship you want using it. The clear problem, though, is that anything you build in the base game will stay the same and probably not do much.
You can, however, look into a number of mods that will add the usual rocket features. You can build small spaceships that you can ride in and go to new places, like the moon, with the Galacticraft mod.
Kerbal Space Program
Kerbal Space Program has to be on any list that has spaceship building and space exploration on it. Once you get the hang of making spaceships that are balanced and work well, KSP is a fun and satisfying game, even if it takes you a while to get good at it.
In this game, realistic, aerodynamic, and orbital physics are given a lot of attention, which makes it a bit unique. But after your first successful launch, you’ll be able to look at other worlds, take resources from them, and study new technologies.
Empyrion Galactic Survival
Empyrion Galactic Survival has everything you’d expect: you can build, explore, fight, play with other people, and explore a 3D world. There are many biological threats from humans, aliens, and other sources to deal with, and the system is strong and lets you move freely.
You can warp between different planets and even land on their moons if they have any. The game does a good job of simulating the variety and vastness of space. Along with the main story, you can also find out secrets about each alien species you meet.
Spore
But in Spore, you won’t be able to start making ships right away. But you will be able to in the future. That is, after you’ve lived as a microscopic organism, changed to living on land, formed a group, and finally built a modern society with enough technology to go to space.
The graphics aren’t great, and the systems and rules aren’t as strong as in most sci-fi exploration games, but Funny Shooter 2 lets you change a lot of things to get the look you want.
Kingdom Hearts
You might be surprised to see Kingdom Hearts on this list. If you’ve played Kingdom Hearts, KH2, or KH3, you probably know about Gummi ships, which are the main way to get from one world to another in the series.
Even though the Gummi Garage is only part of the Kingdom Hearts series, it’s still a lot of fun to build and change your ship however you like. Many colors, pieces, weapons, and stats can be changed, especially in Kingdom Hearts 2. If you haven’t tried it before, you might be surprised.
Space Haven
With its overhead view and single-player mode, Space Haven is very different from the other games on this list. Its gameplay is similar to games like RimWorld and Dwarf Fortress.
You will build and grow spaceships and space stations, but you won’t be playing as a single character. Instead, you’ll be in charge of a group of people who are looking for a new place to live. Just make sure that your amounts of oxygen, CO2, and dangerous gases stay in check as your colony grows.