Exploit?

found a guy today with name (root name) C-Lekktor. Steam - mrkitty.

The problem is he jabbing exactly after he got slashed (after shielding and after recieving damage) and in 95% he doing it.
I am sorry about lite proof with fail, but on the vid i could catch only one moment for 10 minutes of all/ But last 15 minutes before recording there was 2-2 and that guy tired me of with this *feature*. I've never seen this later and dont think it is possible. Extra suspect with he made another account to play with this.

Also i have full record of his gameplay to proove that he is smurfing

 

C-Lekktor is an alt accout of a player named Poseidon_, who has been playing this game for a while (And is notorious for the amount of alt accounts he has made) so don't be too surprised with that he's using advanced techniques.
What you have described (although, couldn't exactly see on the video) is called an instajab. It's a useful feature, that is not very intuitive, which is why it might seem like a bug. I suggest you read about it here:
https://deynarde.github.io/kag-knight-guide/knight-iv-expert.html#instajabs
There are a few of other techniques there you might've seen him use (maybe some that he doesn't know of too), so I suggest you read the whole guide as well. Not only is it very useful, you won't have to deal with that sort of confusion anymore.

 

fwiw "smurfing" does not really have much of an impact, and while i think multiple accounts are against the terms of service i am pretty sure that rule is used to deal with ban evasion, and that isn't the case here