Spore vs Starbound
Spore
Spore is a pretty unique and addictively fun god-mode-like sandbox game where you get to create a whole new world and fill it with your living creations. As a "god", you can play around with the game's five evolutionary stages, from Cell to Space, and grow an entire space-faring civilization from its very simple beginnings as a single-cell organism. Of course, to develop a civlization, you'll need plenty of tools to help them along and Spore gives all of that to you in an easy-to-use format. You can literally customize everything you like in the game ranging from vehicles that your creations will drive or even buildings that your organisms will live in.Although Spore is essentially a single player game - after all, there can only be one almighty god... and that's you! - the world you've created is shared with other players in the game, so your creations can actually explore new planets and maybe even bump into a hostile race which will force them to make the preparations needed to go to war.
Overall, Spore is an amazingly detailed, civilization-building, sandbox game that allows you to micromanange almost everything if you choose to do so, or you could lay down the groundwork and let things unfold by themselves. Best yet, there is no limit as to how many worlds you can create, so unleash your creativity and your godly powers and develop the ultimate civilization today!
Starbound
Starbound is amazingly fun 2D sandbox/exploration game that will put you in the shoes of a spacefarer and a captain of your very own spacecraft. As you travel through space, you will need to stop by planets to collect resources and perhaps even colonize them so you can also gather up a crew to man your ship. There are up to 7 races to play as, a story campaign where you are tasked to save the universe, and 3 different game modes ranging from Casual to Hardcore to either provide you with a fun relaxing experience or to put your survival skills to the test. You can even play the game cooperatively when you want. For modders, you can add in new races, biomes, dungeons, quests and anything else you'd like as well.Starbound can be turned into a pretty much an endless game due to its procedurally generated universe, where you can simply fly around in your spaceship looking for your next big adventure. Thus, you can definitely expect hours of gameplay at the very least for your first playthrough, making this game very well worth its price.