After the battle of Sonic the Hedgehog and Dr Ivo Robotnik at the end of Sonic the Hedgehog, Dr Robotnik promised to remove all his badniks from Mobius. Robotnik was doing as he had promised, or so Sonic thought... Dr Robotnik was secretly double crossing Sonic. He was secretly torturing all of Sonic's friends and was sending meteorites to the planet. Dr Robotnik then went to attempt to steal the Master Emerald from Knuckles. On Robotnik's confrontation with Knuckles, they started to battle. Knuckles tried to fight Dr Robotnik but was sorely defeated and was left for dead as Dr Robotnik stole the Master Emerald. When Sonic found out about Dr Robotnik's double crossing, he severed his new found friendship with Dr Robotnik and went to the Master Emerald. He saw Knuckles dying and Knuckles' last words were: "Sonic...Please get the Master Emerald back and save all of mankind.". Knuckles passed away. Sonic was furious and upset. After crying for a bit, Sonic stood up and lifted his fist in the air and shouted "I will kill Dr Robotnik: In the Final Showdown."