You must first defeat The Hunter. Use the Black suit and it will be easy. You will then catch up with the new and improved Lizard. Stand by a generator and wait until he is about to strike, then dodge. He will hit the generator and shock himself. This will also shock you. Repeat this until you must counter-attack him and ride his back. Use the Left Analog-stick to balance and he will run into one. Then, the last one shuts off and you must turn it back on. Go over to the switch, and if done quickly enough, press Y to turn it back on. Ride his back one more time to defeat him.