The thing is Killian can run pretty fast too. At the Mont Blanc [trail] marathon last month he was holding his own on the first 11 miles or so (pretty flattish and "runnable"). Covered all surges that guys like Max King and Andy Wacker put down on the downhills at 4:50-4:40/mile pace on the smooth trails. I was holding on for dear life until I basically bonked and fell off the lead pack.
We hit a major climbing part on the course (this event had nearly 10,000' of climbing...most in the second half) around mile 12 and he could easily drop Max King on an uphill. A few "mountain guys" like Stian and Luis Alberto and Joe Gray can flat out "short range" climb better...but it depends if the hill is like 15% or 30% grade.
Get to the top of a mountain followed by a technical downhill and Killian is even faster and much better. Max is great at technical downhills and has improved his uphills (he did get 3rd in this race), but Killian really can move fast in the mountains....running...not powerhiking (which is he fast at as well).
It was a surprise to see because he had spent so much time on Everest recently and on skis most of the winter.