This is an old game design document that ended up unused. It's posted here in the hope that readers will find it entertaining at the very least, if not informative. Remember, ideas can't be copyrighted!
Ruler of Andromeda will be a turn-based strategy game with hotseat multiplayer, narrated through a series of tactical spaceship battles. A campaign mode, fleet building and even ship building are all possibilities. Campaigns should of course be able to branch depending on the outcome of each battle.
The players will take turns giving orders to their ships through a menu system. Results may not be visible until a turn or two later. To keep turns interesting, each player should have a handful of ships to command per battle.
Key to the battle system will be range to target (measured in thousands of kilometers). Beam weapons will be insta-hit, but lose power fast with distance. Missiles will be more powerful to begin with, but much slower and liable to be intercepted by point defense. (Also, the more missiles you have in flight at the same time, the worse they perform.) Better engines will help ships jockey for position. Better computers will improve targeting. Better power plants will give bonus actions.
A variety of special effects could spice up battles:
Since the game is designed to be multiplayer, the story must go on after each battle, regardless of who wins (unless presumably the players agree on a rematch). That in turn necessarily means the story must be able to branch. Therefore a campaign must have more battles than the players will see during a single playthrough.
The average number of battles in a playthrough is to be determined based on how long it takes to fight one. Ideally there should be multiple campaigns of different lengths.
Whoever finds themselves on the losing side should still be able to win battles to the end. No death spiral to ruin the fun!
In case the battles by themselves turn out to be repetitive, other elements could be added: recruitable commanders, choosing the roster of ships for certain battles, named ships that carry over and gain experience. A training mode would also be in order, where players can fight individual battles while being able to build up their fleet, or even design custom ships.
Naturally, an AI player would be nice to have down the road.
As described, Ruler of Andromeda will be largely text-based. Any graphics will be more for illustration purposes: static backgrounds, ship images for the battle screen, menu frames and icons... possibly also character portraits for cutscenes.
Similarly, music will be needed for menus, battles, and cutscenes. Futuristic sound effects for command selection and such are readily available online.