During the first stage of the battle, the Northern Military bombarded the base of Alpha-Omega with an attack by helicopters, catching the Alpha-Omega soldiers off guard as they tried to take positions on the fortifications. The Alpha-Omega soldiers fired back with anti-aircraft turrets, blowing most of the helicopters out of the sky. Colonel J. Wesley McCullough was unable to lead the defense due to his infection with the virus from contact with Nova's doll.
Soon, the rest of the Northern Military ground forces emerged from beyond the field and attacked the base with tanks, mortars, and infantrymen, leading to a massive full-scale attack of the base whilst the apes could only take cover from the fighting. After losing all their aircraft, the Northern Army was left with only ground forces to attack the base.
Ultimately, the battle was won by the Northern Military after Caesar threw a grenade on a fuel depot which led to a chain reaction that destroyed the entire base. However, celebrations by the Northern soldiers were cut short when an avalanche caused by the amount of noise generated from the explosion came in and wiped out both human armies completely.
With the human armies subsequently devastated by a massive avalanche, Caesar and the other apes escape and survive by climbing nearby trees. The apes depart the facility and cross the desert to find the oasis, in which they make their new home. During this time, Caesar succumbed to his wound from the battle and died while taking one last look at his kind who were freed from the war.