Factions are the different teams of the Nexus Force. There are four, and each are based off of a LEGO® Universe faction. The players can join a Faction in Bob Plaza, where they receive there Faction Recruit Gear from the faction vendors. The rest of your faction gear can be bought in the Nexus HQ.
Creator

The Creator Logo.
Assembly. They follow the creative Newton Q. Overbuild.
Eclipse

The Eclipse Logo.
Guardians

The Guardians Logo.
bearing a star with six swords coming out of each side. They will be the faction in LNA that focuses on combat skills and strength. They are a division of Sentinels and led by the noble Lord Protectus.
The Expeditioners

The Expeditioners Logo.
They are a division of the Venture League and is led by the adventureous Ferdinard Radboud.
You can to go to each individual faction's page for more information!