If your having trouble with challenge 9, just stand in the bottom left corner and hold down and keep hittin S. after a while the enemies will give in to ur plan and repeat a process in which they run towards u jump and come back. They will hit you a couple times but u should win!
 "Newgrounds Rumble"){kind=icon}
 "Mario's Adventure!"){kind=icon}
 "Mario's Adventure 2!"){kind=icon}
 "Runes of Shalak"){kind=icon}
 "More Mindless Violence"){kind=icon}