There are references to the game Zone of the Enders: The 2nd Runner, which Hideo Kojima also worked on. In Hal's lab, on the northern wall there is a Zone of the Enders: The 2nd Runner poster. This replaces the Policenauts poster for the Playstation version of Metal Gear Solid. The following cutscene with Otacon in which he expresses his love for japanese animation and robots will play footage from Zone of the Enders: The 2nd Runner as well. This also replaces a Policenauts nod from the Playstation version of Metal Gear Solid.