What is a Brutal Execution?

[Dwight Hut Pizza]

So i'm trying to complete a challenge to upgrade one of my vendetta gear and the challenge is to kill a online vendetta target with a brutal execution. What exactly is that? I tried brutalizing one when they were low enough health for me to kill them with it and it didn't complete the challenge. I look in the guide too so I could see if I could find anything on it and I couldn't. Can somebody please help me and tell me what to do?

[Rdven]

Well Brutal Execution is the execution but with 2 might bars full.

The thing is that most times your vendetta target kneels and gives you a speech and after that a final quick combat promt and maybe this does not count.

Fail this combat prompt break him down again and finish him off with full might bars.
Credits: older threads