In the level "Interval 09 - Incursion - Lapdog", there is a secret room that contains a whiteboard texture previously featured in an earlier game developed by Monolith Productions, Shogo: Mobile Armor Division, as well as a radio that plays audio of a news station reading traffic reports in Maritopa, a town from that game, before playing "Negai (Wish)", the game's theme song.
Contributed by MehDeletingLater
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