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One of the great things about GoIO is how much more enjoyable the game becomes when you're playing with a group of friends. But what if none of your real life friends play the game, and the people in your social tab don't always show up at the same time as you do? That's where clans come in. Clans hand you an opportunity to be part of a community within the community, making it so you can always be online with a crew you know and trust. Guns of Icarus Online has dozens of different clans, each with their own traits. You might be interested, for example, in joining the just-for-fun clan X, the competitively-oriented clan Y, or a casual/competitive mix like clan Z. It all depends on what you're looking for and who you enjoy playing with. Some clans enter in competitions to prove their worth against the best opposition. Unlike in other games, the competitive scene of GoIO is extremely accessible. It's not rare for clans to pull off giant-killing performances mere weeks after their formation.
It should be noted, however, that joining a clan isn't an obligation at all. A lot of people enjoy staying out of clans, which means that they'll probably end up playing with a broader spectrum of players. Once again, it's all about your approach to playing the game.
Once you're in a clan, you can add their tag (if they have one) to your name in the social tab. This is currently the only in-game functionality with regards to clans, though other features can prove useful, such as crew formation. Many clans will also use features and programs outside of the game, such as Steam Groups, Teamspeak, or Skype in order to improve communication and organization.
If you're interested in joining a clan, you should check out the
Docks board on the Guns of Icarus Online forum. A number of clans have recruitment threads there, and you can also make your own post in search of crew mates. For an overview of both the major clans and some up-and-coming ones, check out the
Current Available Clans thread for details on each of them.