I would say Tom and Shelldon is rated G, being that it has to do with a 13 year old boy trying to impress his father. Oh, and he does all of this with the help of his best friend slug, Shelldon. In one issue thereāll be a bad guy who uses stink bombs...but I donāt really think you could count that as an actual bomb. And later there might be guns that are shown (as there is an volume with spies). So I donāt know if that bumps the rating up to PG or PG-13.