Is 50 Cent about to put his money where his big mouth is?

On Thursday, the outspoken rapper used the (very popular) ALS Ice Bucket Challenge as an opportunity to dare boxer Floyd Mayweather Jr. to prove he could read.

“This is a special [ALS/ESL] challenge for you, Floyd,” he said in a video posted to his Instagram account. “If you can read one full page of a ‘Harry Potter’ book … I’ll give $750,000 to whatever charitable organization you want to,”

“Without starting and stopping or f—–g up,” he added in the video’s description.

The challenge is the latest chapter in the long-simmering beef between the former friends.

50 Cent (real name Curtis Jackson), 39, has taken much delight in poking fun at Mayweather, 37, and his recent romantic troubles this summer, taking every opportunity to remind the undefeated fighter that his ex-fiancée, Shantel Jackson, left him for the rapper Nelly.

The boxer addressed his many feuds — including the one with another rapper, T.I., whom he brawled with at a Las Vegas Fatburger earlier this summer — in an interview with MLive on Thursday.

“God has blessed me with an unbelievable talent, with fast feet, fast hands, unbelievable defense and a very, very sharp mind. So I’m thankful for that. Of course, hip-hop artists, they come and go. They come and go. But I’m still here,” he said.

Mayweather has yet to accept or decline 50 Cent’s challenge.

Warning: Video contains explicit language.