By 1988, Slayer were already one of the biggest metal bands in the world. 1986's Reign in Blood sent them from the underground to the forefront of the metal scene where they were known as the most sinister of all of their contemporaries.

After working with producer Rick Rubin for the second time, the thrash outfit dropped their fourth effort South of Heaven on July 5, 1988. To the surprise of fans and critics, it had offered quite a different vibe than Reign in Blood had. Still, it's made a lasting impression as part of Slayer's discography, especially with songs like "South of Heaven" and "Mandatory Suicide," which frequented the band's live setlist often throughout their touring days.

To commemorate the release of the album, see eight facts only superfans would know about Slayer's South of Heaven.

1. They discussed making the album calmer in nature prior to writing it.

Jeff Hanneman revealed that due to the success of Reign in Blood, Slayer knew they had to take a different approach when writing its follow-up, rather than try to make the same record twice. Before they started making the album, they discussed slowing it down.

"South was the only album that we actually talked about before we started writing it," he told Decibel Magazine. "I remember we actually discussed slowing down. It was weird. We’ve never done that on an album, before or since."

2. The result was not only slower, but featured new elements to their sound overall.

South of Heaven was the first time Slayer introduced undistorted guitars and more relaxed vocals into their music.

3. It signified a shift in roles within the band.

South of Heaven is the last Slayer album that Hanneman has writing credits for on every single song. Additionally, he and Kerry King were the primary writers on all of their previous albums, but this one saw Tom Araya become more involved in the writing process. Going forward, Araya and King did the majority of the writing on their records.

4. It's the first and only of their studio albums to feature a cover.

"Dissident Aggressor" is a Judas Priest song that Slayer covered for South of Heaven. "It was more just like one of those odd songs that a lot of people didn’t know, but it was a favorite of Kerry and I, so we just picked that one," Hanneman explained to Knac.

It's the only cover they've ever recorded for a studio album — all of the others have been for compilation albums or special releases.

5. It's Kerry King's least-favorite album from their discography.

King had just gotten married and moved to Phoenix around the time that Slayer were recording, so he was not as involved in the process as he had been for their previous albums. He told Decibel Magazine he felt his own performance on it was "lackluster," and admitted he didn't like it as much because of Tom Araya's new vocal style.

6. "Cleanse the Soul" has never been played live.

According to Setlist.fm, "Cleanse the Soul" is the only original track from the album that's never been played live. King admitted to Metal Maniacs that he hates the song, which may explain why. "That's one of the black marks in our history, in my book. I just fucking think it's horrible. I hate the opening riff. It's what we call a 'happy riff.' It's just like 'la-lala-la-la-la.'"

They've also never played "Dissident Aggressor" either, which is a Judas Priest cover. The self-titled track is the one most frequently played live.

7. The cover was part of Larry Carroll's Slayer collection.

Illustrator Larry Carroll, who also designed the covers for Reign in BloodSeasons in the Abyss and Christ Illusion, created the artwork for South of Heaven. 

"I was always told my work was too dark for most folks. So Slayer was a good fit for me," the artist later told Revolver, though he admitted there is no actual connection between the covers he designed. "They each had their own vibe. The input [was] the songs and lyrics — I would comb through them and see what they triggered."

Def Jam Records

8. It was certified gold the same day as its predecessor.

Though they were released two years apart, South of Heaven and Reign in Blood were both certified gold by the Recording Industry Association of America on November 20, 1992.

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