Probly already suggested, but my two cents: Cubed Worlds! That way I can't just mine the bottom/side out of planets easily and all cheap-like. Also, we could mine into them and build bases inside, place defensive turrets all around them.
Also, what about planetary core mining to obtain gravity controlling technology (artificial gravity-style for your ships)? The block can be like the heart of the planet, super special to acquire.
Also, what about planetary core mining to obtain gravity controlling technology (artificial gravity-style for your ships)? The block can be like the heart of the planet, super special to acquire.