I think cinematics are not necessary after first playthrough. You even put them in main menu, why forcing to watch them every time we beat boss level?..
Actually I found secret levels. You have to press the hidden butoon on level select screen: http://img801.imageshack.us/img801/126/secretw.jpg. + so everyone can see.
Sucker punch's silence duration is actually 3 rounds, not 4. Got that hard way when Doom Frog had less 50% hp left =[ Also when it's written "1 rounds remaining" for stun/silence, it actually means that the effect has already ended and after your move enemy WILL do something (or cast something - in case of silence). That's not very transparent... be wary.
"If you beat the game before badges were added, you will need to beat the final level again."
Again?! NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!!!
 "A Duck Has An Adventure"){kind=icon}
 "Utopian Mining"){kind=icon}
 "Talesworth Adventure: The Lost Artifacts"){kind=icon}
 "Random Heroes"){kind=icon}
 "Cactus McCoy 2"){kind=icon}
 "Sleepy Stu's Adventure"){kind=icon}
 "Murloc RPG 2: Episode 1"){kind=icon}
 "BioGems"){kind=icon}
 "Picma Squared"){kind=icon}
 "World Rebellion II"){kind=icon}
 "Epic Coaster"){kind=icon}
 "The Enchanted Cave"){kind=icon}
 "Vehicles"){kind=icon}
 "Take Something Literally"){kind=icon}
 "Kongai"){kind=icon}
Congrats! There should be something new waiting for you in one of the menus ;)