Rapper Fifty Cent and Floyd Mayweather have often, openly and loudly hurled insults at each other on social media, but Floyd’s latest hit back will be rather difficult for Fifty to dodge. The feud is something like a classic rap battle, so when a secret recording surfaced of Floyd struggling to read a line for a radio advertisement, Fifty saw a golden opportunity to deliver a diss of epic proportions.

In a special “ASL-ESL Challenge”, Fifty asks Floyd to read one full page of a Harry Potter book without “stopping or f*!king up.” See below.

Whoa! That’s a solid right-hand uppercut to the jaw, but Floyd isn’t the best paid athlete in the World for no reason. He absorbed the blow like a champ, and he came back with a solid left-hook Tweet to Fifty’s temple late last night.

Knowing that rappers value measurable success the most (cars, money, jets – whatever you can count and fill a music video with), Floyd brags about his exceptional ability to add large positive numbers (specifically, the large positive numbers of his two biggest paychecks in 2014). Know more.