A check of the road signs will tell you that Ozzfest Meets Knotfest was taking place in California, but as the weekend festival wound down, Slipknot were in an "Iowa" state of mind. As Corey Taylor stated, the band were in San Bernardino to play their iconic IOWA album in full for one night only, and it was an awesome 15th anniversary present that most Slipknot fans would not forget. After the pre-show song "Dream Weaver" from Gary Wright wound down, the drape in front of the stage fell and the audience was met with a blistering visual and audio assault with "People = S--t" leading the way.

Though certain elements of their stage set remained modern, the band's red jumpsuits from the era were back in full effect. And the fans were fully into the special performance with the crowd audibly singing over the band at certain points. Tracks like "Disasterpiece" and "My Plague" kept the energy level up, while "The Heretic Anthem" chant of "If you're 555 / Then I'm 666" was one of the high points of the set. Given that the band was revisiting IOWA, this meant there were several rare performances planned. "The Shape" received its live premiere, while "Skin Ticket," "New Abortion" and the title track, which served as the encore, were all played for the first times in over a decade.

Thrash icons Slayer preceded Slipknot, and like several of the bands on the bill, their set was constricted a bit due to technical difficulties and delays that plagued the Lemmy Stage bands earlier in the day. But Slayer made the most of their time with a set that mixed newer tracks like the show opening "Repentless" and "You Against You" with classic cuts like "War Ensemble," "South of Heaven," "Raining Blood" and the set closing "Angel of Death." The foursome of Tom Araya, Kerry King, Gary Holt and Paul Bostaph had one of the more visually interesting stage setups, featuring a darkened bluish and purple backdrop with occasional yellow lighting and a perfect amount of pyro providing a very psychedelic look that at times was reminiscent of a blacklight poster come to life.

With Amon Amarth, it would be very easy to be distracted by the band's giant Viking ship set piece, one of the most elaborate stage props in modern metal. But there is so much more to the band's set. The Swedish metallers have the songs to warrant the adulation, with tracks like "Twilight of the Thunder God" and "Deceiver of the Gods" leading the way and newer songs like "First Kill," "The Way of Gods" and the fun closer "Raise Your Horns" blending in perfectly. Add in the synchronized hair flips, Johan Hegg's punching the air and lots of energy and they definitely provided one of the Lemmy Stage's top sets.

Elsewhere on the Lemmy Stage, the aforementioned delays really affected what fans saw. Anthrax took the biggest hit, only getting in five songs before having to move on. While they were onstage, they delivered "Caught in a Mosh," "Fight 'Em 'Til You Can't" and "Indians" with plenty of energy, but the shortened set kept them from playing any For All Kings material. Trivium got in a set fairly close to what was expected, with "Strife," "Until the World Goes Cold" and the set closing "In Waves" among the highlights. And Motionless in White opened the Lemmy Stage after a long delay with a set featuring such standouts as "Death March," the current single "570," "Break the Cycle" and "Reincarnate."

Meanwhile, out on the Monster Energy and Nuclear Blast stages, it was a tough day for the bands, who soldiered through high temps combined with major wind and dust whipping through the area. But that didn't dampen the rock. Westfield Massacre opened the day with a high energy set, complete with synchronized hair whipping and hard rocking. They certainly left an impression, as did Japanese rockers Man With a Mission, who delivered a blend of melodic pop metal and hip-hop, all while wearing an assortment of animal masks. The band showed the enthusiasm of a group happy to be there, but also one ready to make their mark. And there was definitely a buzz for Oni, as word got out before the weekend that Lamb of God's Randy Blythe was set to join them for their set. Though Blythe may have drawn some festival goers to the early day performance, Oni held their own once the guest turn was done and they sufficiently built some anticipation for their Ironshore album.

Other highlights from the side stages included a memorable set from Butcher Babies, who incorporated a fire-breather into their stage show while playing "Monsters Ball." Heidi Shepherd has previously expressed her love for the pit, and both she and Carla Harvey took turns making their way into the crowd during their set. They definitely received one of the biggest responses of the day. Meanwhile, Suicide Silence braved one of the dustiest sets of the day and the audience loved them for it, chanting "Suicide" repeatedly in appreciation of the band. Tracks like "Unanswered," "F--k Everything" and the set closing "You Only Live Once" all got solid responses.

All in all, Ozzfest Meets Knotfest gave fans a lot of bang for their buck, with hard rocking outfits in all sorts of styles giving it their all while making sure this rare festival collaboration lived up to the hype. Black Sabbath's final California performance and Slipknot playing a rare full-album salute to IOWA might be enough to satisfy some metal fans, but with standout sets from established acts like Disturbed, Megadeth, Slayer and Amon Amarth, there were plenty of memories to be made.

See photos from the Knotfest Day of Ozzfest Meets Knotfest by scrolling through the gallery above, and revisit our recap and photo gallery from the Ozzfest Day by clicking the red button below.

(Report by Loudwire contributors Chad Childers, Kathy Flynn and Alex Kluft)

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