Here are some tips of how to get the hard badge, First off remember how the track goes, when they are playin the choruses, there are a lot of jumpers, when they arent, there arent many, and make sure u perform different stunts everytime, cuz if u do the same stunt over and over again, ur multiplayer wont go up, the highest you could get on regular is x6, and on pilot mode, its doubled, so try to get to pilot mode when you have x6 multiplayer, and goodluck, hope my tips help, if it did, + it to keep comment alive of how to get the hard badge easily.
 "Vector Stunt"){kind=icon}
 "Ballpark Fun"){kind=icon}
 "Popeye Jigsaw"){kind=icon}
 "Doodle God"){kind=icon}
 "Platform Racing 2"){kind=icon}
 "Guess Geography: U.S. States"){kind=icon}
 "Factory Balls 4"){kind=icon}
 "Neon Race 2"){kind=icon}
 "Animal RaceWay"){kind=icon}
 "Bear in Super Action Adventure"){kind=icon}
 "Dojo of Death"){kind=icon}
 "nolan is god"){kind=icon}
 "Sugar, sugar 3"){kind=icon}
 "Papa's Freezeria"){kind=icon}
 "Earn to Die 2: Exodus"){kind=icon}
 "Bouncing Ball"){kind=icon}
 "Mia Car Accident"){kind=icon}
 "Block Life"){kind=icon}
 "Super Crazy Guitar Maniac Deluxe 3"){kind=icon}
srry about that