The new record features collaborations with the likes of Dr Dre, Ty Dolla $ign, DJ Premier and Skylar Gray, along with nods to coronavirus.
It also includes an apology to singer Rihanna, referencing a decade-old song that leaked in 2019, in which Eminem spoke about 'siding with Chris Brown' after he pleaded guilty to felony assault in 2019.
In the new song, titled 'Zeus', he raps: "But, me, long as I re-promise to be honest / And wholeheartedly, apologies, Rihanna.
"For that song that leaked, I'm sorry, Ri / It wasn't meant to cause you grief.
"Regardless, it was wrong of me."
Responding to the leak at the time, Eminem's rep also claimed he and Rihanna actually had a good relationship, and that he later rewrote the song.
His spokesperson Dennis Dennehy said in a statement: "This is a leak of something that's over 10 years old. After Eminem recorded it, he scrapped it, and rewrote it. Obviously he and Rihanna have a great relationship."
Elsewhere in 'Zeus', Eminem - whose real name is Marshall Mathers - also takes a swipe at Tekashi 6ix9ine, saying: "She says I am trash, but she listens to Tekashi."
Oh, and Snoop Dogg: "As far as squashing beef I'm used to people knocking me / But just not in my camp / And diplomatic as I'm tryin' to be / Last thing I need is Snoop doggin' me.
"Man, Dogg, you was like a damn god to me / Man, not really, I had dog backwards."
Announcing the release of Music To Be Murdered By - Side B earlier today (Friday 18 December), Eminem wrote on Instagram: "Uncle Alfred heard you screaming for more... enjoy Side B."
The record is the follow-up to Eminem's 11th studio album, Music To Be Be Murdered By, which came out in January.
After being released with no warning, the surprise album featured guest appearances from Young M.A., Royce Da 5'9", Q-Tip, Denaun, White Gold, Ed Sheeran, Juice WRLD, Skylar Grey, Anderson Paak, Don Toliver, Kxng Crooked, Joell Ortiz and Black Thought.
It debuted at number one on the Billboard 200, and sold 279,000 units in its first week - in turn meaning Eminem became the first artist to have 10 consecutive albums debut at number one in the US.
That time around, one of his tracks addressed an ongoing feud with fellow musician Machine Gun Kelly.
In 'Unaccommodating', he rapped: "When they ask me is the war finished with MGK? Of course it is / I cleansed him of his mortal sins / I'm God, I'm the Lord, forgives even the devil worshippers."
Featured Image Credit: PA
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