User blog comment:Bennlimos/HxH Questions & Thoughts Discussion 11/@comment-5780397-20150511101832/@comment-5780397-20150511214038

8) Considering that a lot of Hunters have gone missing, my guess is that Pariston is a Specialist that can somehow steal the abilities or the strength of Nen users he kills, or that he just enjoys fighting (and since he appears unscathed, he must be strong). Most likely both things.

9) The funny part is that I wrote "he would most likely have offered his/her own life"