NEW YORK -- Over 20 years after their formation, Slayer remain one of the most menacing, brutal and skilled acts in heavy metal. They're also one of the most unlikely success stories. The band's songs aren't rooted in vocal melody like Black Sabbath's, and they're not anthemic like Judas Priest's or multifaceted like Metallica's. They're sinister, bludgeoning and played at one of two speeds -- fast and lightning fast.

From the moment they emerged in 1982, playing underground hardcore-based metal that glorified the devil, Slayer have made their own rules with little thought about their public profile. Moreover, they've stood true to their sonic and social convictions. They haven't changed with the times or matured with age. In fact, they've hardly aged at all.

Reign in Blood, arguably their best album, was released more than 18 years ago, and most of their current Jägermeister Tour show is made up of songs released before 1990. And yet, Slayer are hardly a nostalgia act. They've still got the rage and hunger of youth, even though the members -- frontman/bassist Tom Araya, guitarists Kerry King and Jeff Hanneman and drummer Dave Lombardo -- are in their 40s. And while they stubbornly adhere to the same type of '80s thrash metal they helped pioneer, their music isn't the least bit stale or anachronistic.

Before the launch of the Jägermeister Tour, it looked like Slayer's set would feature Reign in Blood in its entirely, capped by a shower of fake blood from the rafters (as the band did for its current concert DVD, "Still Reigning"). Instead, Slayer opted for a greatest-hits showcase that ended with three songs from Reign in Blood. As a result, the performance displayed more range than it otherwise might have. Slayer revved into thrash-metal overdrive on soundblurs like "Fight Till Death" and "War Ensemble," and dropped the pace on moodier numbers like "At Dawn They Sleep" and "Dead Skin Mask."

As the band emerged Thursday night for "Disciple," the stage was flooded with smoke and decorated like a creepy church altar. During the show, flags with red inverted crosses and the group's Teutonic eagle-and-pentagram logo were unfurled, and later a backdrop of shots from Reign in Blood descended. But the group could have performed without any frills (as it did on Ozzfest) and still have destroyed. Years of experience surely have something to do with it, but Slayer's ferocity stems largely from their chemistry. When King and Hanneman stand side-by-side, trading off whirring riffs and strangled-cat solos while headbanging in tandem, they're as lethal a team as serial killers Henry Lee Lucas and Otis Toole. And no frontman can windmill his head and play bass as viciously as Araya, who has recently been plagued with vocal problems, but who sounded great for the entire show.

After plundering through "Hell Awaits," "South of Heaven" and "Angel of Death," Slayer encored with "Postmortem" and concluded with "Raining Blood." As the latter reached its climax, the crowd stared at the ceiling, expecting crimson showers to cleanse the band, but only a drizzle dropped from the sky. It was unclear whether there was a malfunction or if Slayer downgraded the downpour at the orders of the venue or to avoid getting drenched. Regardless, it didn't matter. The band continues to create enough sonic thunderstorms to fully irrigate the sometimes-barren metal landscape.

Opening act Killswitch Engage stirred the crowd with a contemporary set that combined scathing metalcore and blinding Swedish death metal. Killswitch's greatest strength is their ability to shift at will between angular rhythms, start-stop riffs and hooky vocal passages reminiscent of Fear Factory. Half of the band's nine-song set was culled from its most recent album The End of Heartache and the other tracks were from its second disc, 2002's Alive or Just Breathing.

Singer Howard Jones, clad in a baseball cap, alternately jogged and jumped across the stage as he sang, Mike D'Antonio stabbed the sky with the headstock of his bass and guitarist Adam Dutkiewicz surged his axe forward while strumming, as if digging for platinum. Clearly, Killswitch Engage have their moves down. As they ripped through cuts like "Breathe Life," "Fixation on the Darkness" and "Rose of Sharyn," they proved their unconventional metal is just as convincing.

For more sights and stories from concerts around the country, check out MTV News Tour Reports.