The Notum Wars
Anarchy Online received its first major upgrade, labeled a "booster pack" by Funcom, in late November 2002. It has since been packaged with the core game. This expansion introduced one of the major components of the game's player vs. player system, the towers. In this expansion, players and their organizations (AO's name for player guilds) became capable of building towers on specific land areas across Rubi-Ka. These towers include a central controller and an array of defensive towers, which typically confer bonuses to individual players or their organizations, or which confer penalties on invading players. These towers would regularly become open to attack by players of opposing factions, who, after successfully destroying the towers of their enemy, could claim the land as their own.

 
The Outzone playfields, part of Alien Invasion
The Shadowlands
Perhaps the most well received of Anarchy Online's expansions, the Shadowlands presented a tremendous new world, collectively called the Shadowlands, which is the last remnant of the world Rubi-Ka was before it was wrenched apart in the game's fiction by a dimension-breaking cataclysm in ages past. Enriched in notum, this diverse world is inhabited by vestiges of the ancient races that lived on Rubi-Ka, called the Redeemed and the Unredeemed, as well as a giant, world-reaching computer, named Ergo, who recognizes character races as descendants of the past and whose motives in propelling players through the Shadowlands are ambiguous at best.

Released in September 2003, the Shadowlands expansion was well-received critically.[2][3] In addition to the tremendous world the expansion added, it also introduced significant changes, improvements and additions to virtually every aspect of the game, including music, character development, items and interface.

 
One of the player-controlled mechs available with Lost Eden
Alien Invasion
Building on the storyline introduced in The Shadowlands, Alien Invasion was the next expansion to the Anarchy Online game. This expansion introduced player-built cities, player-owned shops, new social interactions and clothing, and, most significantly, a new threat to the world of Rubi-Ka in the form of an alien race that has suffered tremendous pain and death because of human interference in the Shadowlands. It was released in September, 2004.

Lost Eden
Lost Eden is the title of Anarchy Online's fourth expansion pack. The expansion was released in mid-December 2006. The expansion focuses on player vs. player elements and adds a variety of new features, including player-controlled robotic vehicles, additional arenas and attacks, additional items that can only be acquired by spending points awarded for winning conflicts, and the option of dedicating experience towards gaining new abilities rather than levels. Much of Lost Eden's content has been, and continues to be, released in subsequent content patches.