If you take Spelljammer as canon, the mass of a planetary body doesn't matter, earth average gravity is a universal constant. Toril, Oerth, Krynn and all Spelljamming vessels have the same gravity.The only thing I need to know is what is toril’s gravity. and how much would I be able to lift and how far could i jump If i took a portal to Oerth. Also how fast could I run. Because I am thinking of creating a character on faerun and hopping a gate to either oerth or Mars.