Here we have Hell Awaits.
Still a definite classic, though, I experience this one as sort of bland meat between the awesome bread of Live Undead and Reign in Blood. Opening with the much feared backward masking of the era, the album goes on to present pounding, but long compositions, a highly compressed sound, effects like flanges and delays and lyrics that get kind of dumb in parts (see "blood sucking creatures of the night"). But hey, it's fucking Slayer!
Here's a great video from just after the album's release. I prefer this live version. This whole concert used to be available on VHS, also featuring Venom's set from the same night. Not sure if it ever made it to DVD. I hope so.