Actually i have done more HS-chain kills than the video.... (But im not hacker

)
The main crux of the video to show that he's hacking...
Notice and pls focus at 0:09, at that blind corner, if no hacks are used, its impossible to predict that red se wolf is jumping on him, and he's pre-shooting at the corners of metal barrels <Notice the slight sparks at barrel>
Verdict: Hacker.