The island is located somewhere south of North Korea's coast, numerous NK Bases dot the perimeter of the island populated by hundreds if not thousands of KPA troops, along with several enemy tanks and APCs that patrol between them. A few AN transport planes were shot down across several remote areas of the island and survivors have camped out at the sites waiting to be rescued, constantly hounded by Chang's soldiers.
The island has seen extensive research into chemical and biological weaponry, and consequently, a few areas of it have been contaminated with radiation and the only way of passing through these areas unharmed is by riding inside a "shielded" vehicle like a tank or APC. When the mercenary receives clearance to hunt down Chin Chang, he/she is sent to the island with two objectives: verify the Ace of Diamonds, and destroy the KPA's Type-07 Supergun.
The Supergun is a titanic artillery platform capable of firing radioactive shells from Seoul all the way to Tokyo, it is the epitome of Chang's research into chemical/biological weaponry. Perhaps realizing how vulnerable it was, Chang installed a radar jammer into the weapon to prevent any kind of heavy weapon from striking the Supergun. Furthermore, the area around the weapon is irradiated, making it rather difficult to approach without sufficient protection. Unfortunately for Chang, he set up the Supergun within striking range of a prototype supergun just above a cliff overlooking it, the mercenary takes advantage of this and utterly destroys the Type-07, after which Chang makes one last stand against the mercenary at a nearby outpost, guarded by several men and T-62 tanks.