Set after the events of The King of Fighters 2003, the story focuses on a group known as "Those from the Past", who aim to obtain the power of the ancient demon Orochi.

The game retains the gameplay elements from The King of Fighters 2003 involving fights between six characters who can tag between members during battle.

[4] There is also an Edit Mode, where the player can alter the appearance of each character and give them different colors such as making Kyo Kusanagi shoot green flames instead of red.

[5] During the events of The King of Fighters 2003, Mukai, a member of a mysterious group known as "Those from the Distant Land", stole the seal belonging to the demon Orochi.

Taking advantage of this situation, Ash Crimson attacked Chizuru Kagura in her weakened state and stole the Yata Mirror from her, draining her powers in the process.

[8] In the ensuing chaos, Ash attacks a rampaging Iori Yagami (affected by his Riot of the Blood curse) who had seriously injured both Kyo Kusanagi and Shingo Yabuki, managing to steal the Yasakani Jewel from him.

Despite being confronted by his estranged childhood friend Elisabeth Blanctorche and her two associates Benimaru Nikaido and Duo Lon, Ash manages to swiftly escape from them, warning the trio that he intends to target Kyo as his final victim in the near future.

[9] SNK cancelled production of The King of Fighters 2004 in the fall of 2004, after it was announced the company had signed an agreement with Sammy Corporation to use their arcade system instead of the Neo Geo cabinets that had been used for the franchise previously.

[11] SNK commented that by using this new system, The King of Fighters XI would stand out from its predecessors due to improvements in both gameplay mechanics and graphic quality, specifically the animation frames created for Iori Yagami.

[14] The addition of mid-bosses from Buriki One and Kizuna Encounter were meant to surprise gamers; since their original moves did not "fit" in The King of Fighters XI, developers had to change some of them.

[15][16] In 1999, SNK released a Fatal Fury installment named Garou: Mark of the Wolves whose narrative lacked closure.

[13] The movements of the boss character Magaki – the leader of the group of antagonists "Those from the Past" – were intentionally designed to "disgust and disturb fans".

[21] With respect to the progressive scan, SNK explained that the North American version of the game was based on the PAL region.

[26][27] On March 24, 2006, Scitron and SNK released The King of Fighters XI Sound Collection (ザ・キング・オブ・ファイターズXI サウンドコレクション), a soundtrack from the game.

[28] Since the PlayStation 2 was being replaced by a new console during the release of The King of Fighters XI, Gamasutra listed the game as one for the "hardcore gamer".

[39] However, in its release week in Japan, The King of Fighters XI was the only PlayStation 2 title to be featured on Japanese sales charts alongside Konami's World Soccer Winning Eleven 10.

[41] Critical reception to The King of Fighters XI has been "generally favorable" based on an average score of 75 out of 100 on the Metacritic website.

[34] Andrew Park of GameSpot opined that the game was well-balanced with its variety of playable characters and complimented its illustrative design.

[33] While noting the artificial intelligence had improved from that used in The King of Fighters 2003, uVeJuegos.com said Magaki had unfair moves due to his massive damage input during battles.

[35] In a retrospective review, HardcoreGaming regarded The King of Fighters XI as one of the best entries in the franchise, noting the backgrounds' quality, the gameplay and quick load times compared to the original arcade game.

[44] Writer Akihiko Ureshino lamented Mai Shiranui did not make it to the game canonically but was satisfied with her inclusion in KOF: Maximum Impact 2 as a meaning of compensation.