The Battle of Gunung Merah occurred in 2010 when the communist Reapers paramilitary assaulted the Gunung Merah radar facility in the Lautan Lama Desert amid the Panauan Civil War.
After Roaches boss Razak Razman's nephew went to trial amid Panau's civil war, the Panauan Army procured a false witness who could convict Razman's nephew. Bolo Santosi - boss of the rival Reapers gang - hired the mercenary and undercover CIA agent Rico Rodriguez to gain information from the Gunung Merah Radar Facility, track down the false witness, and take him to Santosi, who could use the witness' testimony to blackmail Razman. Rodriguez single-handedly infiltrated the radar facility and took the opportunity to wreak havoc, destroying its fuel depots and other military infrastructure before killing an officer, using his keycard to access the mainframe, and downloading the witness' information. Rodriguez was able to track down the witness, hijack his vehicle, and take him to the Reapers, who used him as leverage against the Roaches.