- "There is a Samurai inside all our hearts. That is the place where he awakens and fights. The arena."
- — Nogmung —
The Arena is an area for PvP combat located on the Omega Server. Unlike the PKing that occurs in other parts of The World R:2, all combat in the Arena is consensual. Some guilds exist solely for Arena competition. As items cannot be used in the Arena, Harvest Clerics and other casters are considered invaluable.
There are three Arena circuits by level, called Palaces. In the Japanese version, the name of each Palace was preceded by the worlds Crimson, Cobalt, and Dragon respectively, seemingly referring to the Epitaph of the Twilight.
In the Arena, teams of up to three players fight against each other in organized matches. Successful wins earn each team points, which increase their rank in their arena Palace. After a certain period of time, the top 16 teams in a Palace will face each other in a tournament. The winner of this tournament then holds an exhibition match against the current Emperor. Whoever wins becomes the current Emperor of that palace, and will keep that title as long as they continue defeating challengers. A player can only be an Emperor of one palace at a time.
Demon Palace (紅魔宮)
Holy Palace (碧聖宮)
Sage Palace (竜賢宮)
- All Arena matches are overseen by a mysterious Commentator. Little is known about this man, not even if he's a CC Corp employee. His peculiar nature has earned him a small fan club. Occasionally he invites other players to announce with him, usually a high-ranking officer in one of the combatant's guilds.
- In Redemption, a team of PCs among the many random Sage Palace opponents called the Super Mod Squad are PCs named after and designed by Namco Bandai's .hack//G.U. forum moderators, Ichida, Viscosity, and Leon.
- Thanks to an online event at ALTIMIT Corporation, winners were chosen to have a team of 3 PCs named after them in Redemption. Their team can be found ranked #1 as The Sweepstakers.