Games like Empyrion: Galactic Survival
Space Engineers
Space Engineers is a sandbox game about engineering, construction and maintenance of space works. Players build space ships and space stations of various sizes and utilization (civil and military), pilot ships and perform asteroid mining. Space Engineers utilizes a realistic volumetric-based physics engine: all objects can be assembled, disassembled, damaged and destroyed.
Sky Break
Sky Break is an open-world game on a stormy abandoned planet filled with wild mechas. Learn to master this world and to hack the mechas if you want a chance to survive.
Star Control: Origins
The Earthlings have joined the interstellar club. The galaxy will never be the same. The year is 2086 and Earth has detected an alien distress call originating from the surface of Triton. In response, Star Control is formed with you as The Captain of Earth's first prototype starship.
Force of Nature
Force of Nature is an indie open world sandbox game with fighting, crafting, building and farming systems.
Life is Feudal: Your Own
Hardcore medieval multiplayer sandbox with terraforming, free preset and modular building construction, rich crafting (smelting, forging, farming, animal breeding etc.), survival, no target physics based combat, original combat formation system and numerous other features. Taking place in the fictional medieval world, game imposes a realistic system of global politics, economy, and socialization.
Rising World
Rising World is an open-world sandbox game with randomly generated, fully destructible environments. Starting with the most basic of tools, collect resources to survive in the wildness. Evolve your world to create one of the biggest cities of all time or a gigantic castle, or simply let your imagination run riot! If being creative is all too much, just connect with your friends and get them to help. Rising World is a procedurally generated world, with fully textures landscapes, over 200 different building materials, loads of tools and many other items to help you create OR destroy your world without any restrictions.
Starmade
StarMade is a 3D sandbox space shooter created by Robin "schema" Promesberger, founder of Schine. The game allows players to explore the vastness of space; building factories; creating ships, space stations and structures out of various block types. Both single-player worlds and multi-player servers are available players. StarMade is currently in Alpha, and is a free-to-play game.
Dude Simulator
Dude Simulator is an open world sandbox game. This is a life simulator. The main objective is to enjoy what you are doing.
Grav
GRAV is a sand box experience where you explore a multitude of planets, hunt strange alien creatures, build and defend outposts, craft weapons and armor, and attempt to survive against other players in a hostile environment.
Miscreated
Miscreated is a multiplayer online hardcore survival game set in a post-apocalyptic future. You will need to survive against mutants, players, and even mother nature herself.