Board Thread:Skyrim/@comment-11344160-20130718190551/@comment-6881629-20150912172108

They all depend on your equipped weapon and random chance the list is here, for that move (it's flourished slice i think) you need to be using a one handed sword (you might also need the other hand empty but not sure). If your on PC mods like [http://www.nexusmods.com/skyrim/mods/56980/? VioLens] will let you fiddle with the kill move settings.