SM&LA: Ep. 6
Bowser works on becoming his giga self, and Mario and Luigi enter the biathalon in Water Land.
This is the sixth episode of Super Mario and Luigi Adventures.
Credit to the respective sprite and background owners. (credit to 041 for the Yoshi sprites)
Episode Five: http://scratch.mit.edu/projects/Stitch33/1529870
UPDATE: Bowser's Outside Story, the spin off series will have a Paper Mario like battling system, and a Mario RPG dialogue system.