Use what you've learned about moving to get the cat to run the bases (as realistically as possible - bases are run counter clockwise) in baseball.sb. Make sure that when you click the green flag, the cat starts at home plate again.
I changed the cat sprite, to a 16 bit Jigglypuff sprite. I added 58 glide blocks to make Jigglypuff run around the field, changing costumes as well. I also added music and another sprite in the end.