After Dr. Eggman throws Homer into Jail, Bowser have took over the Mishima Zaibatsu. In the end, Mario & Luigi won the King of Iron Fist Tournament 3. Now after the King of Iron Fist Tournament 3, Dr. Eggman is ready to unleashed Eggbots, until he noticed that Homer Simpson is back & he destroys every single Eggbot. Now Vezon opens the King of Iron Fist Tournament 4.