Today is the the fitness exam at Billy and Mandy's school and Nergal Jr. is competing, too. He can change his shape and size, so it makes the whole exam easy for him. Billy asks Nergal Jr. to turn into some pants for the last part of the exam, which is a jogging contest. Billy runs at amazing speed, but there's a little problem....he can't stop runnning! So Billy runs all over the world and is known as the fitness lad.
Grim scythe starts to get kind of dull, so he trys to get a new one. He is told that there's an upgrade to his old scythe: Scythe 2.0. Scythe is forced to do all of Billy and Mandy's chores by Grim, but when Scythe 2.0 gets angry at the kids, he decides he needs to kill Billy and Mandy. Grim wanted to do it, so he goes after it.