So this run is very hard since you need to do 3 pretty precise jumps in the tunnel (The one grabbing the mega mushroom, the one where you slide with your butt and the one bouncing off one of the spineys) and even if you get everything in one run and a (maybe) perfect pipe entry of 261 you need to do the final stair jump also perfectly. Funnierwise I practised that run in before for half an hour and couldn't get it but when I recorded it I got it second try :D