Apophis

Apophis is the giant serpent of chaos, the eternal enemy of the sun god Ra and the great adversary of cosmic order. He dwells in the dark depths of the Duat, the underworld through which Ra sails his barque each night. There Apophis rises to attack, trying to swallow the sun and plunge creation back into the formless void. Every night the gods aboard the barque fight him off: Set hurls his spear, others slash his coils, and the cat-headed sun slits his throat. He can be wounded and repelled but never truly killed, returning to threaten the dawn again and again.