Rainbow Six Siege, Ubisoft’s online tactical shooter, is set to get a makeover. The company announced a “new era” of Siege with Rainbow Six Siege X Monday, promising major changes to gameplay in an upcoming update.Rainbow Six Siege, Ubisoft’s online tactical shooter, is set to get a makeover. The company announced a “new era” of Siege with Rainbow Six Siege X Monday, promising major changes to gameplay in an upcoming update.