This is a player who will specifically trade for the alliance. There are 2 categories of traders, the first one is an experience trader, this person trades routes that will make experience quickly but might not be able to make good money. These players are important to an alliance as they can be able to cloak over other traders late in the game in either a Death Cruiser if they are evil or a Dark Mirage if they are WQ Human race. The other type of trader is a money trader, often nicknamed a cash cow. This type of trader will trade long distance profitable routes, these types of routes can be sometimes found between planet galaxies and neutral galaxies. Often these traders will fly small jump ships like the Inter-Steller Trader or the Advance Courier Vessel.
These players are very important to an alliance and an alliance's defense. They will spend their turns usually daily or every other day filling force stacks with mines that were left by other players in the alliance. Some common ships that are used for this task are the Human Border Cruiser or the Thevian Carapace. If you are not Human or Thevian, there is a neutral option for mining, that is a Battle Cruiser. Also sometimes used for mining is a Death Cruiser though this is an Evil only option.
Hunters are essential to an alliance's early success. These players normally trade only for a day or so before getting into a ship that is hunter class with scouts and/or mines. Hunters will hunt down enemy traders and kill them for their trade profits they have made while trading and/or to keep preferred trade routes open for their own alliance. Some popular ships that are used for this task are the Ik'Thorne Advance Carrier, Human Border Cruiser, Thevian Carapace and Salvene Ravager. Also for good players there is the Federal Ultimatum and for evil players the Death Cruiser is an option, though both of these ships are more expensive due to their multiple roles.
A builder is an extremely important role to any large alliance with a planet galaxy. This person or people will build planets in a regular rhythm such that the planets build as quick as possible. Also these players along with other traders in the alliance will stock the planets with trade goods needed to build the planets. A couple of common ships used to help build the planet galaxies are Alskant Deep-Spacer, Human Ambassador, Human Border Cruiser, and Inter-Steller Trader. The key importance of all these ships is that they all have jump drive which means they can easily get to a planet galaxy and back to a federal protected sector undetected by jumping from one to the other.
This role is important in the middle to later parts of the game. These players are normally in warbirds or strong hunter class ships. They are used to help bust ports via port raids and planets via planet busts. Oppers normally will have to sit for a couple days to build sufficient turns to help out in the busts and raids. Normally in an op against an opposing alliance these players will have to clear mine fields with their ships which is why saving of turns for a couple of days is key. These turns can be used very quickly clearing mines and unoing