Warning: Article contains NSFW language.

The ongoing feud between 50 Cent and Floyd Mayweather Jr. took another petty turn Thursday when the rapper issued his own version of the ALS Ice Bucket Challenge in the name of mocking his former friend.

In a video posted to his Instagram account, 50 Cent challenged Mayweather to read a page out of a Harry Potter book, saying he'd donate $750,000 to the charity of Mayweather's choice if the boxer completed the task.

Warning: Video contains NSFW language.

"This is a special A-S-L…E-L-S challenge for you, Floyd," 50 Cent said. "If you can read one page out of a Harry Potter book, n----r, I’ll donate $750,000 to whatever charitable organization you want to…f--k the bucket of ice, man!"

The rapper managed to muck up the terms "ALS" (amyotrophic lateral sclerosis) and "ESL" (English as a Second Language) in his monologue. He also misspelled "accept" in his caption of the video—an ironic misstep considering his challenge's implications.

Another video posted shortly after the initial "challenge" Thursday shows 50 Cent saying late night host Jimmy Kimmel had contacted him with an offer to allow Mayweather to read on Jimmy Kimmel Live!

Warning: Video contains NSFW language.

"Got a phone call from my man, Jimmy Kimmel," 50 Cent said. "Jimmy said that if Floyd accepts the challenge, he'd put it on the actual show. You can read it on the show. We don't want to put pressure on you, we know you can't pronounce those words in that Harry Potter book. So we're going to let you read Cat in the Hat."

The highly public deterioration of 50 Cent and Mayweather's friendship has been going on for years, starting with a 2012 squabble over the rapper's involvement in Mayweather Promotions.

This particular outburst, however, appears to be rooted in comments Mayweather made in an interview with MLive.com's David Mayo earlier in the month.

The boxer told Mayo that rappers fade in and out of relevance, while he remains the constant.

"God has blessed me with an unbelievable talent," Mayweather said. "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…but I'm still here."

Mayweather went on to say that rappers lie about their wealth and use his name to bolster their brands— ostensibly insinuating that 50 Cent only beefs with him for publicity.

In any case, it's clear that a new, low bar has been set in the 50 Cent-Mayweather feud. Trading barbs in the media is one thing, but twisting a charitable effort into a personal attack is a singular type of ugly.

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