There is a problem with interplanetary civilizations: developing them takes more resources than a single planet can offer, and sometimes even a planetary system is not enough. Especially if you have competition.
In distant cosmos, two sister planets have reached a rather tense situation. The ancient greed, inherent to both civilizations, has driven them to most dramatic measures: the building of massive cannons, aimed directly at each other. Let the game of interplanetary artilleries begin!
Gameplay
Interplanetary is a turn-based strategy game for PC, Mac and Linux, featuring both single- and multiplayer modes. It is inspired by classics like DEFCON, Civilization series and old-school artillery games.
Your goal is to cause damage to the enemy's planet and to protect your own. Manage your planet's infrastructure using the limited natural resources and research new technologies to develop even mightier weapons and defenses.
At the end of each turn, there is a chance to shoot your interplanetary guns and try to hit major strategic points on the enemy's planet. Be precise, and you might manage to navigate your railgun slug around other planets and their gravity wells, straight into enemy cities!
http://www.indiedb.com/games/interplanetary
That says it all, what do y'all think?