In my opinion that game is a spin-off because of the title Super Paper Mario.


I think it's the eighth video game in a long line of Mario platformers you see there's Super Mario Brothers, Super Mario Brothers II, Super Mario Brothers III, Super Mario World, Super Mario 64, Super Mario Sunshine, New Super Mario Brothers, Super Paper Mario, and Super Mario Galaxy.


I'm not counting Super Mario RPG : The Legend Of The Seven Stars or Mario & Luigi : Superstar Saga because those games aren't platformers those games are RPGs.