Fatal Fury Special
In the planning stage of "Fatal Fury Special", another SNK fighting game, Hattori Hanzo of "World Heroes" was being considered as a hidden boss. However, Hanzo was a character developed by another company. Even though ADK was a subsidiary, the staff decided instead to place Ryo as a hidden character; they found him more interesting as a guest character. Ryo's addition to "Fatal Fury: Special" was done with the approval of the designer of the first "Art of Fighting" game who also worked on designing Ryo for this game.