SPOILER ALERT: This chapter explains, in details, how the Pirate Guild AI is behaving. Reading this may spoil a part of the fun discovering the plugin by yourself. If you are new to this plugin, I'd suggest you to play for a while and go back here when you want to know more about how things are done.
Unlike other factions in the game, the Pirate Guild has its own economic system based on raids. The more raids and attacks from the Guild are successful and the stronger the Guild will be. However, to keep the plugin CPU friendly, calculations have been somewhat simplified. So instead of using real credits, Pirate Guild uses virtual money. As an example buying a M3 will cost 500 credits to a pirate base, a M4 400, and a laser-tower about 1000 credits. The pirate bases will earn money in different ways. When they successfully raid a trading vessel, the pirates will collect some wares and get a proportional amount of virtual credits. So pirate guild's bases have a strong tendency to attack transports with a valuable cargo. On top of that, the Guild itself has a bank account used to buy special items (like a M2, or some M7 to defend the pirate base network). This account is funded with donations from wealthy pirate bases.
The player can contribute to the Guild's expansion by giving ships and money to the various Pirate Bases. If you have a lot of money to spend you can also deploy news Pirate Guild Outposts. To do so you'll have to dock a TL at a Pirate Shipyard, buy the Pirate Base and build it whenever you want. After a while it will be taken over by the Pirate Guild.
Also, as Pirate Bases deals in more wares, you'll see more trading ships going (lured would probably a better word, according to their survival rate) to and from pirate bases.
In Pirate Guild, each Pirate Base works on it own. Strategically well placed ones will usually grow bigger when other one may be destroyed and relocated. When the plugin is started or when a new PB is created, the plugin will give several ships, money, and new wares to this base. Then, each base will periodically -depending on settings- perform an action. According to its current situation (overall strength, available ships, money, target availability + some randomness), it will choose one of the following courses of action. Also notice that PB will usually try to focus on targets owned by the guild's current enemy faction.
In addition to this big and wealthy Pirate Bases may also decide to spend money in building a Pleasure Dome, a station where you can sell your illegal wares for a decent price and play blackjack. They can also build a M7 that will be used by the Defense Grid system (see below).
Pirate Bases will dynamically change name according to how well they are currently doing. Notice that in the lowest difficulty setting, there's no stronghold or fortress.
Pirate Guild is more than able to defend itself against any threat, even if the said threat if from the player himself.
In pirate sectors (or other sector with a pirate base inside) you will find Pirate Guild patrol ships. They act very differently from standard patrol ships you can see in-game. In fact, they are looking for pirate ships being attacked by ships from other factions (including yours) around them. When such a ship is found, all pirate ships patrolling the sector will attack the enemy vessel. When the enemy has been vaporized, they will resume the patrol. If you are a friend to the guild, they will also protect your own ships.
In addition to patrol ships, wealthy Pirate Bases will protect themselves by buying laser-towers and M6 corvettes. Major pirate bases will also do some active defense by attacking potential threats. With enough funds the Guild is able to buy a single M2 and several M7 that will be called for help by pirate bases when under attack. Pirates Bases are allowed to build jump beacons nearby so the M7 frigates and the M2 destroyer won't have to travel all the way from the gate to the attacked base. This defense system is called the Defense Grid, and it's very similar to how the RRF plugin from LV works.
Last but not least, if you have the Anarkis Defense System script installed, a new option will be available in the setup menu which allows you to enable this feature on pirate bases. This is a very effective defense system where the Pirate Base will coordinate its ships to defend itself. In other words, the pirate base will send wings before the incoming enemies are in firing range.
All these mechanisms make a Stronghold or a Fortress very hard to destroy. Don't expect to remove one of those with a single puny M2, you will need a whole fleet to do so, and you may loose several ships during the battle.
The Guild's Mothership is a M1 Galleon Carrier. At first the Galleon will fly from a Pirate Base to another in order to recruit pirate fighters. When its docking bays are full, it will start attacking the current “Worst Foe” of the Pirate Guild faction. It will jump in a random enemy sector and deploy its fighters for a large scale raid. After each sector invasion by the Galleon, the “kill counter” of the targeted race is divided by 2, and the M1 will go away for a while doing repairs and refueling. If the M1 is destroyed all “kill counters” will be reset, and after a while the Guild will buy a new Mothership. This works against the player, too.
Wealthy strongholds may build a Mob Boss flying in a M6 heavy corvette. This special ship patrol in sectors around the Pirate Base and attack transports with a good cargo. When attacked by stronger opponents, it may decide to flee. The Mob Boss is also able to ask his homebase for fighters support during fights. The bounty put on a mob boss usually increase quickly, so killing him can be very rewarding for the player.
Mob Bosses run an improved combat AI, they can call for reinforcements and jump out to safety when facing possible destruction.