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In December 2004, Falcoon, the series' main illustrator, said the next game SNK Playmore were developing would be different from the recent spin-off "", which was originally intended to be released as "The King of Fighters 2004". Development of the game began when SNK completed production on the crossover game "NeoGeo Battle Coliseum" in 2005. 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. "The King of Fighters XI" arcade version used Sammy Corporation's Atomiswave system. 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. However, it lacked the AW-net, a program that allows for online play. SNK had previously tested this system for both "NeoGeo Battle Coliseum" and "The King of Fighters Neowave".