King of Fighters R-2, is a fighting game released by SNK in 1999 for the Neo-Geo Pocket Color handheld system. It is the only game from the King of Fighters series released for Neo-Geo Pocket Color. It is the sequel to King of Fighters R-1 for the Neo-Geo Pocket, a previous generation of the handheld.
Like most other King of Fighters games, King of Fighters R-2 features various SNK characters. This game, based on King of Fighters '98, has the main character going up against Rugal Bernstein as Rugal is creating clones of the main characters.
Source: Wikipedia, "King of Fighters R-2", available under the CC-BY-SA License.