When Snake talks with Director Granin in his office, the theme playing on the radio is the Metal Gear Solid theme. Also, the specifications he shows to Snake are of Metal Gear REX from
Metal Gear Solid (1998) (VG). There are also figurines of Metal Gear REX, Metal Gear RAY from
Metal Gear Solid 2: Sons of Liberty (2001) (VG) and Jehuty from
Zone of the Enders Z.O.E (2001) (VG) visible in the background, along with a photograph of Granin with his American friend (the grandfather of Hal Emmerich, Metal Gear REX's chief engineer in the original Metal Gear Solid).
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