Thornax was created when N-70 fired a Growth Mutagen Cannon at Speewaa and Jorbyy, the shot missed and struck a thornax bush. Thornax was the result. N-70 would later recruit Thornax to help him kill Speewaa, Jorbyy, Spaunauh, Koukou, Thulox, Morak, and Suction-cup. He followed Speewaa's group to their camp, and attacked them. Unbeknownst to him, a Biobite Serpent had been stalking them as well. Speewaa and her allies fought valiantly, but Thornax knocked Jorbyy unconscious and trapped Thulox, Morak, and Koukou in a cave. However, the Biobite attacked Thornax, and while Thornax fought the snake, Speewaa took the opportunity to escape along with everyone else.