How does the band that wrote "Reign In Blood" try to top that album? The answer: You don't. You create something different.
I'll spare you why "Reign In Blood" was/is so influential and important to the Metal scene in general, and SLAYER wrote whatever they wanted to (I'm assuming), but to re-write its faster, heavier and more extreme version would probably sound forced and unnatural.
Enter "South Of Heaven". From the slow, haunting, melodic intro riff that starts off the title track, you can tell that SLAYER has matured. They realized that forcibly going 200+beats per minute for most of an album would make it redundant and boring, due to lack of dynamics (well, most of the time). Heaviness can also be achieved with dissonant melodies or a slower, more chord-based riff, and the band decided to plod into those territories as well.
Speed is not altogether gone from this album, though. "Silent Scream", "Ghosts Of War" and "Cleanse The Soul" are all at warp speed, the way that SLAYER showed the Metal world to do. However, being the only 3 songs that are blazing fast, they stand out from the rest (also, each has a different 'style' of riffing and song structure, plus the tempos vary a bit) of the album. Making each song longer also always them to develop better, making each one distinct and memorable in its own right.
The riffing has also gotten more technical than before, forgoing the simple tremolo picked chromatic chaos that was featured on "Hell Awaits" and "Reign In Blood", and goes for a more interesting mixture of the aforementioned tremolo picking and down-picked notes, making the music far more interesting than before. I'm not saying that the songs on this album are anything of technical genius of MARTYR's or DEATH's calibre, but the musicianship has improved. Added also is a sense of subtlety present in the melodies (anyone ever notice the SECOND guitar line in the intro of "South Of Heaven"?).
Tom Araya has also started to SING, instead of just screaming his lungs out like he used to, adding further dimension to the songs, and making it more memorable. The solos actually start to make some musical quality to them, compared to the random flurry of whammy bar dives and endless notes (I don't want to go on a rant about why SLAYER solos have always fit the music, but that's another topic, and too long to dwell into).
Furthermore, the legend of Dave Lombardo was born on this album. The crazy fills he throws in during nearly the entire album (Listen to "Behind A Crooked Cross" and "Silent Screams" for the best examples). He truly starts to shine on this album, moving away from the fast yet rather monotonous drum beats of "Reign In Blood" (in come the flurry of hate mail……).
This album has aged truly gracefully, showing a band that has matured both lyrically and musically, and one that is full of unsung classics. (Online October 18, 2003)