Hip-hop is notorious for its bravado, but bad boy CEO Martin Shkreli is one-upping rappers over their own work.

The pharmaceutical mogul -- last year nicknamed the most hated man in America for massively hiking the price of a vital drug for HIV patients -- is the sole owner of the Wu-Tang Clan's "Once Upon a Time in Shaolin."

Shkreli, who was recently indicted on security fraud charges, on Thursday threatened to edit out contributions on the album by Ghostface Killah after the Wu-Tang member insulted him.

"I expect a written apology," Shkreli wrote on Twitter. "At least 500 words, no grammatical errors and Shaolin stays intact."

Shkreli also taunted Ghostface Killah in a video in which the 32-year-old New York businessman sips from a drink surrounded by three masked men who brandished a silver box said to hold the album.

"I'm going to erase you from the record books of rap," Shkreli said, calling the 45-year-old Ghostface Killah "an old man that's lost his relevance."

"You have to listen to me," he said. "Without me, you're nothing."

His threat came after Ghostface Killah referred to Shkreli with a profanity when speaking to the gossip site TMZ.

The rapper, who appeared to be speaking extemporaneously after being approached on a Los Angeles street, denounced Shkreli for the 5,000-percent rise in the Daraprim drug's price.

Ghostface Killah said that "Once Upon a Time in Shaolin" should belong instead to "the people" but said the issue was out of his control.

The influential New York rap ensemble had made only one copy of the album, which was stored in a vault in Morocco until Shkreli bought it for $2 million.

RZA, generally seen as the leader of the Wu-Tang Clan, earlier said that the sale of the album was completed before the infamous price hike and that some proceeds would go to charity.

Shkreli may have been imitating a video in July in which Ghostface Killah threatened younger rapper Action Bronson for criticizing the elder rapper's recent output.