|You know what to do! Get out there and kill 'em all!|
After the mysterious deactivation of the Electric Perimeter Fence, this enabled hordes of Warrior Bugs to break though and commence the attack, accompanied by Bombardier Bugs and at least one Scorpion Bug. The Mobile Infantry garrison were quick to be called into action and moved toward the Arachnid incursion. However, at least one platoon was routed by Bombardier Bug and Warrior Bugs. The maze-like layout of the military base on Roku San proved extremely hazardous for these routed soldier, as panic and crowding meant a lot of troopers were easily picked off and killed.
Meanwhile, Colonel Rico and his personal squad of troopers encountered a flanking force of Arachnids. Due to precise and excellent military tactics and basic manouvers, they were able to drive back the force and inflict moderate casualties. Rico's squad eventually pushed back the Arachnids far enough so that they are able to reach the Command Bunker, where Lieutenant Link Manion and her fellow troopers had been valiantly fighting to keep the Arachnids at bay.
Meanwhile, General Dix Hauser managed to locate Sky Marshal Omar Anoke, and with the help of Anoke's personal Marine Corps, they managed to make it to the boat. General Hauser requested to stay on Roku San to detain Colonel Rico for insubordination, due to Rico's intervention which saved the life of a farmer.
Meanwhile, Colonel Rico and his troopers were attacked by an incoming Bombardier Bug, which destroys a great portion of the frontal wall. A second Bombardier enters the gaping hole, during which one soldier sacrifices himself by jumping onto the Bombardier Bug just as it detonated. The troopers then faced a new problem in the form of the arrival of a Scorpion Bug. The Scorpion Bug proves it's power by killing three troopers with the plasma generated from its tail. Rico then fired a grenade at it's tail, enraging the Scorpion Bug. It redirected its tail at the roof of the bunker firing a plasma burst that caused the Bunker's roof to collapse, trapping the soldiers inside.
Eventually, Roku San defense line was destroyed in one night. Fortunately, Rico, Manion and other survivors were rescued after the battle. However, Colonel Rico was blamed for the defeat.