Stillaguamish, S. Fork - 2 - Mallardy Creek to Verlot (Middle) (WA)
This is the big drop on the run. At moderate flows it is class III but it can push class IV at higher flows. It is traditionally scouted on the shuttle drive up at highway mile 14.6. There are a few different lines and your preferred line may change with the flows so take a look on the way up.