Monster X

Monster X is a villain in Godzilla: Final Wars.

Biography
Under the control of the Xiliens, Monster X was sent to Earth to battle Godzilla. Mothra and Gigan soon appeared as well, with Mothra aiding Godzilla while Gigan aided Monster X. Gigan subdued Mothra and teamed up with Monster X to fight Godzilla, but Mothra returned and destroyed Gigan when she was set aflame and collided with Gigan, destroying him (though Mothra appears to survive during the end credits).

With Mothra and Gigan out of the fight, Godzilla continued to fight his assailant, and soon gained the upper hand. However, Monster X soon transformed into an even stronger enemy: Keizer Ghidorah.

Keizer Ghidorah
Keizer Ghidorah brutally attacked the King of the Monsters, and easily subdued him. The creature then proceeded to bite Godzilla and absorb his very life force. However, the Gotengo fired a beam at Godzilla, giving him the power of Keizer. Godzilla then proceeded to maim Keizer Ghidorah and launch him into space, blowing him up into millions of pieces.