A couple of years ago nobody knew him in the Boxing World except of a few hardcore fans but now He is on his way to become a Star in the sport and needs a badass nickname. Just like Matthysse became the Machine once he started knocking out guys with a pulse, GGG sounds stupid and just stands for his three names.
Here are some suggestions -
Seek and Destroy
The beast from the east
Mayhem
The Karaganda Killer
Thoughts?
By goodboy he meant lol good guy that's how russians talk when you translate it from russian to english it becomes kinda funny. I went to Russian highschool in 80s and 90s lol.