The WWE caravan rides into its next Pay-Per-View on May 22 at the Prudential Center in New Jersey for Extreme Rules. The main event has Roman Reigns putting his WWE World Heavyweight Championship on the line against AJ Styles.History is in favour of the challenger as Extreme Rules has crowned a new champion five times in its six-year existence.So will AJ get lucky as well?? Here is a list that might inspire AJ to defy the odds against Reigns ? all the five WWE/World title changes that occurred at the PPV.