He is rather easy to defeat; he only takes three hits to die. Don't hit him from the front, for he just eats the items Blinx shoots at him. Use a pause and hit him from the side. Then when he gets back up, he will jump attack at Blinx. Blinx can simply stand on a ledge in the back, for Kerogon cannot jump there. Then repeat twice more, and he will die.