Sigma Head

Sigma Head is the first boss of Mega Man X5. He wounded the character opposite the player chose (e.g. X if the player chose Zero, and vice-versa), and hid inside a statue in the background. It's a giant head of Sigma that sends out small energy spheres from its mouth or energy spheres from the eyes. He can also attack by ramming to the character across the screen. After losing half of its energy, it will also send large beams from its mouth. It is only vulnerable at the cannon that appears when the mouth opens. After this boss is destroyed, Sigma's real plot is revealed.

Then that X/Zero have defeated him, Zero discovers that he lose to him in purpose maybe because he was full of the Sigma virus so the earth was completely covered by its explosion.

Similar enemies

 * Sigma Virus