rembo: There are two version that are similar to what you described. First there is 'Growth Ray Mayhem' drawn by K9Wolf / GoblinHordeStudios that he did as a commission to Redsaber. For that one, look through Redsaber's Gallery on Furaffinty (
First Page. The second one is drawn by Manthomex on Deviant art. Just search his gallery for that one.
First Page
I put the links to the first page for each.