The routes up Little Decker come from nearly all directions and are in the Class 2-3 range.  

From the north via Alpine Way Trail (Class 2-3)- ascend the Grand Mogul-Decker ridgeline from any number of slots on the east side after leaving the Alpine Way Trail.  Obtain the summit by ascending the small summit block from the east or northeast.  

From Redfish Inlet Transfer Camp Trailhead: 4.9 miles and 3972 feet gain (one way)

From the north via Outside Chance Valley (Class 2-3)- ascend the Grand Mogul-Decker ridgeline from the Outside Chance Valley, northwest of the peak.  The easiest slots are closet to the peak, while the more challenging slots to reach the ridge, are closer to the Grand Mogul. 

From Redfish Inlet Transfer Camp Trailhead: 3.8 miles and 3614 feet gain (one way)