During the early development stages of
The King of Fighters '99, SNK planned to exclude Iori and Kyo to the game, as the story's focus was meant to center on the new protagonist,
K'. However, they retracted this decision because of the popularity of the characters.
[8] Iori's repeated appearances in the series is due to the marketers and main planners' insistence to add him, Kyo, and other SNK regulars in every game—making it a challenge to decide the story for each title.
[9] Because of his popularity amongst fans, some of the main designers for the series have stated that he is "difficult to draw for".