This game is still either in Early-Alpha or Beta (or any status in between) but IS already available for sale / early access, so CAN BE PLAYED.
Spark Rising is a sandbox action strategy game where you build fortresses and fight back against an invasion. You can build fortresses, weapons, creatures with our voxel game engine, and then take all that into battle. Imagine a game where you can explore and conquer floating fortresses across the galaxy created via user generated content. In addition to user generated content, the game features upgrade systems, co-op gameplay, and a robust story mode.