.hack//G.U. Vol. 3: Redemption is the third and final game in the .hack//G.U. trilogy. Player's once again control Haseo, a player-killer killer in the fictional online role playing game "The World". The game's story continues from where Volume 2 left off. AIDA, a deadly virus, continues to cause trouble in both the online world and the real world. Haseo will need to figure out the truth behind the virus and defeat it in order to save himself and his friends. As with the previous games, the story unfolds through a series of cut scenes as well as by e-mails you'll receive and by reading The World's online message boards. Since the game is a continuation of the previous installments, many of the locations, dungeons, and characters return along with several new dungeons and characters. If you have completed the previous games, data can be transferred in when you start this volume giving you an advantage.

The game uses a battle system which is similar to the previous games; it is in real time and is activated after Haseo comes in contact with an enemy while exploring The World. Up to three members of your party may join a battle; the player always controls Haseo while two additional members are computer controlled. Simple orders can be given to the computer controlled characters to guide their actions. Once again several attacks are available including a regular attack, charge attack, and various skills. After performing a series of combos, Rengeki attacks are available which inflict more damage. The most powerful are awakening mode attacks which require a certain amount of points on your morale gauge. New to this game is Avatar Awakening which replaces the Divine Awakening from the previous game. Avatar Awakening allows you to use the power of your avatar to perform Data Drain on your opponents which will be particularly useful in fighting the virus. Successfully winning battles will earn experience points which allow Haseo and other characters to level up and become more powerful. Many missions, side quests, and dungeons are available with various enemies to fight and to help continue the story.