Question:  Hydra is an album by Within Temptation and contains guest appearances by an American metalcore vocalist best known for being the vocalist of what two bands?

full_context: Document 1: Craig Jones (musician): Craig Michael Jones (born February 11, 1972), also known by his nickname "133", is an American heavy metal musician. Born in Des Moines, Iowa, he is best known as the sampler and keyboardist in Slipknot, in which he is designated #5. Jones joined the band in 1996 shortly after the recording of "Mate. Feed. Kill. Repeat.", replacing Donnie Steele on guitar, although he quickly moved onto the role of sampler. Following the departure of Joey Jordison in 2013, Jones is now the second longest-serving member of Slipknot.
Document 2: Dark Passion Play: Dark Passion Play is the sixth studio album by Finnish symphonic metal band Nightwish, released on 26 September 2007 in Finland, 28 September in Europe and 2 October 2007 in the United States. It is the first album without original vocalist Tarja Turunen, who was dismissed in 2005, as well as the first album involving future member Troy Donockley on uilleann pipes and tin whistle. It is the first of only two albums with vocalist Anette Olzon, who was eventually dismissed in 2012 after the release of the band's subsequent album, "Imaginaerum". Tuomas Holopainen has referred to it as the "album that saved his life".
Document 3: Jesse Leach: Jesse David Leach (born July 3, 1978) is an American musician from Providence, Rhode Island, and is the lead vocalist of the metalcore band Killswitch Engage. He also fronts the stoner rock/heavy metal band Seemless, as well as handling vocal duties for the hardcore metal bands The Empire Shall Fall and Times of Grace. In February 2012 he rejoined Killswitch Engage following the departure of vocalist Howard Jones in January 2012. He currently resides in Brooklyn, NY with his wife, Melissa.
Document 4: Hydra World Tour: Hydra World Tour was a concert tour by Dutch symphonic metal band Within Temptation in support of their sixth studio album, "Hydra", released by Nuclear Blast on 31 January 2014. To date, it was their eight major tour and their third to see them playing worldwide. The tour passed over four continents and was divided into several legs according to the local of playing, presenting minor setlist variations from concerts of the same leg and a few more variations from leg to leg. A special leg was entitled "Theatres on Fire", in which saw the band playing seated shows exclusively on theatres. The tour was commercially successful and managed the band to play on even bigger spaces, an improvement already seen on their last world tour, as well presenting their first concert at the Wembley Arena and selling out theatre tickets for their theatre seated concerts in the Netherlands. A live album with footage from the Amsterdam concert was released later in 2014 under the name of Let Us Burn – Elements & Hydra Live in Concert.
Document 5: Hydra (Within Temptation album): Hydra is the sixth studio album by Dutch symphonic metal band Within Temptation. It was released on January 31, 2014 in Europe and on February 4, 2014 in North America. The album contains guest appearances by singer Howard Jones (ex-Killswitch Engage), rapper Xzibit, metal vocalist Tarja Turunen (ex-Nightwish) and alternative rock singer Dave Pirner (Soul Asylum). The first single, "Paradise (What About Us?)", was released on September 27, 2013, and featured Turunen as guest vocalist. The second single, "Dangerous", was released on December 20, in which Jones provided the male vocals.
Document 6: List of Dark Passion Play editions: Dark Passion Play is the sixth studio album by Finnish symphonic power metal quintet Nightwish, released on September 26, 2007 in Finland, September 28 in Europe and October 2, 2007 in the United States. It was the first Nightwish album with the band's new lead singer, Anette Olzon, and the first album not featuring former vocalist Tarja Turunen, who was dismissed in October 2005. Lead songwriter Tuomas Holopainen has referred to it as the 'album that saved his life'.
Document 7: Enter (Within Temptation album): Enter is the debut studio album by Dutch symphonic/gothic metal band Within Temptation, released by DSFA Records in 1997. The album prominently features lead singer Sharon den Adel's vocals as well as guitarist Robert Westerholt's gruff death metal growls. Lex Vogelaar, founder of the Dutch death metal band Orphanage, supplied the guitar parts for "Pearls of Light", as well as producing the album, and Orphanage vocalist George Oosthoek performed some of the growls on "Deep Within".
Document 8: Adam Jones (musician): Adam Thomas Jones (born January 15, 1965) is a three-time Grammy Award-winning American musician and visual artist, best known for his position as the guitarist for Tool. Jones has been rated the 75th Greatest Guitarist of all time by the "Rolling Stone" and placed ninth in "Guitar World's" Top 100 Greatest metal Guitarists. Jones is also the director of the majority of Tool's music videos.
Document 9: Jonathan Davis: Jonathan Howsmon Davis (born January 18, 1971), also known as JD and JDevil (or J Devil), is an American musician best known as the leading vocalist and frontman of the nu metal band Korn.
Document 10: Corey Taylor: Corey Todd Taylor (born December 8, 1973) is an American musician, singer, songwriter, actor, and author, best known as the lead singer and lyricist of the American heavy metal band Slipknot and the American alternative metal band Stone Sour.
Document 11: Whole World Is Watching: "Whole World Is Watching" is a song by Dutch symphonic metal/rock band Within Temptation from their sixth studio album, "Hydra". It was released in Poland as the third single from the album on January 22, 2014 and was scheduled to have its main release on February 21. The song features guest vocals from Dave Pirner of Soul Asylum, with Polish rock singer Piotr Rogucki of the band Coma providing vocals on the Polish version of "Hydra".
Document 12: Justin Hawkins: Justin David Hawkins (born 17 March 1975) is an English musician and singer-songwriter, best known for being the lead singer and lead guitarist of The Darkness, alongside his brother, guitarist Dan Hawkins. Heavily influenced by classic hard rock and heavy metal bands of the 1970s and 1980s (particularly Queen, Aerosmith, Def Leppard and AC/DC), Hawkins is noted for his falsetto singing voice and on-stage persona. He was also the lead singer and guitarist for the band Hot Leg, formed in 2008, and now on hiatus. Since 2005 he is also active in his synthpop alter ego British Whale.
Document 13: What Have You Done: "What Have You Done" is the first single from Dutch symphonic metal/rock band Within Temptation's fourth studio album "The Heart of Everything" (2007). The song features guest vocals from Life of Agony's lead singer Mina Caputo (then known as Keith Caputo) and it was released as the album's first single in early 2007 (see 2007 in music). It became their first charting single in Canada and in the United States. A new edit/version of the song was released in the U.S. through iTunes on 26 June 2007.
Document 14: Eva (Nightwish song): "Eva " is the first single of Finnish symphonic metal band Nightwish's sixth studio album "Dark Passion Play". It was the first release to feature the band's new singer, Anette Olzon, following Tarja Turunen's departure in 2005.
Document 15: Howard Jones (American musician): Howard Jones (born July 20, 1970) is an American metalcore vocalist, best known as vocalist of the bands Killswitch Engage and Blood Has Been Shed, and as the current vocalist of Light the Torch, formerly known as Devil You Know.
ground_truth: Killswitch Engage and Blood Has Been Shed