As Eminem prepares to release his highly-anticipated seventh album 'Recovery,' the production lineup grows more and more stacked.

Already boasting collaborations with top-shelf beatmakers -- Just Blaze, Dr. Dre, DJ Khalil, Jim Jonsin and Boi-1da -- Em, who generally handles his production himself, revealed a surprising addition to the lineup yesterday, announcing that Queensbridge rapper/producer Havoc has made the cut, unbeknownst to Havoc himself.

"I honestly didn't think I was gonna make the project, but when I heard I did, I was definitely happy about it," the Mobb Deep member told MTV . Havoc said that he has attempted to land beats on an Eminem albums for years, but was surprised that his "dark-sounding" track finally made the cut this time around.

"When it came to him, it's like, I really didn't want to give him a track that he was already kind of familiar with rhyming to," Hav said. "I just wanted to do me and doing me consists of doing all kinds of different styles than what they associate me with, which is dark-sounding. The track that I did for him, it's dark and at the same time it can go across the board as far as the content in the sample and what it's saying. I try to think outside the box but not go too far with it. I think I met myself somewhere in the middle, and I hit him with a track and it worked."

Havoc recently dropped his second solo album, 'The Hidden Files,' while awaiting the release of his imprisoned partner in rhyme, Prodigy.

Eminem's 'Recovery' is scheduled for a June 22 release. Boi-1da produced track, 'Not Afraid, was leaked yesterday to mixed reception.

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