Expansion: Congratulations! You've just cleared out that annoying Station full of bandits. Now what? Well, you can spend 5 Food to colonise any station you currently have a unit in, regardless of whether or not it is connected to a Station you own. However, Stations owned by you but not connected to your capital by an unbroken line of owned Stations are given a timer based on how disconnected they are and various other factors. If you don't connect them to your capital before that timer runs out, it will become a de-facto independent faction, with its own small military and resource stockpile.
There is a, somewhat temporary, solution to this. A Ranger Squad can establish a Ranger Outpost in any Station with no hostile entities already within it. A Ranger Outpost costs 1 Filter to maintain for each turn it is active. You can not exploit any resources or create anything within a Ranger Outpost for as long as it remains active, but as it still places the Station under your control it can be useful for connecting otherwise un-connected pieces of your faction together. It can also be turned back into a Ranger Squad whenever you desire, though a Ranger Squad can not move after forming or packing up a Ranger Outpost.
Finally, the violent form of expansion: Conquest. While it is simple enough to just overwhelm an opponent and take what they already have, a Station that has just experienced a battle may not survive entirely intact. Depending on the scale of the battle, the number of units fighting, the size of the fight and what units are fighting, a D50 will be rolled, with various modifiers, to decide what percentage of the Station was damaged. For now destruction will only affect Resource production, but in the future it may also negatively affect various upgrades and the stability of the Station.
Diplomacy/Trade: 1 Bullet can be traded for 2 Resources and 4 Resources can be traded for 1 Bullet. This trade takes place in an open market and is somewhat inefficient. One way to get around this inefficiency is by creating a Trading Station, which costs 2 Food. Trading Stations can only be created in Stations with Natural Resource generation, and are more efficient at Trading the Resource they generate. For example, a Trading Station that produces Food will allow you to give them 1 Bullet in exchange for 3 Food instead of the normal 2. However, a Trading Station acts as a neutral entity with its own military, so you can not move units into or through it. Doing so will be treated as an act of aggression and will lock you out of trading with any Trading Station for a certain number of turns, as well as leading to a battle in the Trading Station in question. If you win you conquer the Station and become permanently distrusted by all other Trading Stations, if you lose that Trading Station will attempt to fortify any direction you can reasonably reach it from. On the other hand, keeping a good
reputation with them might convince them to give you even more Resources than they normally would...
Of course, you could figure out your own trade deals with other factions, so long as there's a safe route for you to get to each other by, but can you really trust them? Well, sort of. While there are no rules around Diplomacy, leaving the terms of any treaties up to the players in question to follow, I can imagine people will be far less trusting of factions who have previously broken written agreements, so Diplomacy is pretty much self-regulating. I might figure something more solid out in the future, but that's all for now.