A six-year gap for most bands would be daunting, but the circumstances surrounding Slipknot's time away would sink many a group. The death of bassist and key creative member Paul Gray nearly felled the band, which had to take its time to mourn and learn how to move forward without Gray's input and presence. However, as evidenced on their new album, '.5: The Gray Chapter,' even with the losses of Gray and ousted drummer Joey Jordison, the band is as vital as ever.

As expected, '.5: The Gray Chapter' heavily references Gray and the emotions the band went through in the wake of his passing. Beginning on the album opening 'XIX,' frontman Corey Taylor references, "I don't want to get back up, but it might as well be today." The song itself builds in intensity and like other passages on the disc, the heaviness of the music often matches the depth of the emotion.

Another track that owes a debt to Gray is 'Skeptic,' which offers the sentiments, "I won't let you disappear / I will keep your soul alive if I can't keep you here" and "The world will never know another man as amazing as you." 'Goodbye' is perhaps the most telling reference dealing with immediacy of Gray's death, as Taylor solemnly belts, "Well there's nothing to lose so now I have something to say / Maybe we can all recognize a moment of silence / Maybe we can finally agree on the same point of view / A long time ago we believed that we were united / So the last thing in the world I am ready to say is … Goodbye." The album also features some soul baring vocals from Taylor on the darkly moody album closer, 'If Rain Is What You Want.'

But it should be noted that '.5: The Gray Chapter' is more than just about saluting the band's late bassist. There are also a lot of the trademarks that have made Slipknot great over the years. The incredibly heavy and rapid fire drumming gives us such future moshpit monsters like 'Sarcastrophe' and 'AOV.' The percussionists also step up to the plate with some pummeling moments on the single 'The Devil in I' and the album's first preview track, 'The Negative One.' Guitarists Jim Root and Mick Thomson get their chance to shine on such tracks as 'Nomadic' and 'Killpop.' And Sid Wilson's scratching and high pitched samples stand out on ''Sarcastrophe,' 'Custer' and 'The Negative One.'

As usual, this mix of all the different sounds somehow comes together to create a musical journey. And while '.5: The Gray Chapter' definitely rocks and pummels you in all the right places like you would hope, it also shows a depth in emotion and some heavily personal moments on a much grander scale, as well.

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