After X has defeated two of the Maverick bosses in MMX2, the X-Hunters will be spurred to take action. Serges, along with his colleagues, can be found in a secret room in any of the eight stages. When encountered during this period, he rides atop a hovering platform with spikes on its rim. The platform periodically generates a shield that will reflect all attacks and also lays land-mines from its underside. Serges will occasionally attack by jumping into the air and firing a circular spread of energy projectiles. His weakness is the Sonic Slicer obtained from Overdrive Ostrich.
During his battle against X at the X-Hunter base, Serges operates a large machine equipped with four cannons that each fire a different projectile. Four platforms moving up and down in the room. The floor is also lined with spikes, which can make this battle a bit tricky. He attacks by firing a variety of energy balls and laser beams from the four cannons mounted on the front of the vehicle, after two of the cannons are destroyed he will close in destroying two platforms in the process. After, the remaining cannons are destroyed, the front of the machine will be blown open and Serges will continue to attack by firing large energy bullets (that split four ways) via the small cannon mounted on the bottom of his cockpit. The Giga Attack is very effective, as it is one of the quickest ways to tear the machine open to expose Serges. Charged Silk Shots, Sonic Slicers, Speed Burners, and Magnet Mines are also good choices. Especially Sonic Slicers are just as effective as the Giga Attack in destroying the cannons and ripping the machine open.
After the machine has been blown open, stand on the bottom part of the tank below Serges' cockpit and keep hitting him with fully charged Sonic Slicers. His projectiles can still hit X, but they rarely will as long as the player does some simple dodging from time to time; X is also relatively safe from being knocked onto the spiked floor.
- Among the Mega Man X fanbase, it has been speculated that Serges might be a Reploid incarnation of Dr. Wily. Supporting this theory is the fact that Serges masterminded the plan to rebuild Zero after his first death and, in the Japanese version of Mega Man X2, refers to X as the "last memento of Dr. Light" before he dies. The Japanese instruction manual for the game further supports this theory as Serges' profile states that he "resembles a legendary mad scientist who once terrorized the world".