Just two months after lead guitarist [[Dave Mustaine]] was fired from [[Metallica]] due to [[Alcoholism|drinking]], drug use, violent behavior and personality conflicts, Mustaine, bassist [[David Ellefson]], guitarist Greg Handevidt, and drummer Dijon Carruthers formed Megadeth in Los Angeles. Mustaine later said, "After getting fired from Metallica, all I remember is that I wanted blood. Theirs. I wanted to be faster and heavier than them".

In June 1988, Megadeth appeared in [[Penelope Spheeris]]' documentary film ''[[The Decline of Western Civilization II|The Decline of Western Civilization II: The Metal Years]]'', which chronicled the [[Los Angeles]] heavy metal scene of the late 1980s, mostly focusing on [[glam metal]]. The video for ''In My Darkest Hour'' was filmed by Spheeris (who also directed the "Wake Up Dead" and "Anarchy in the UK" videos), and appears in the final scene of the movie. In Megadeth's 1991 ''Rusted Pieces'' VHS, Mustaine recalls the movie as a disappointment, which aligned Megadeth with "a bunch of shit bands".<ref>''Megadeth: Rusted Pieces'' VHS, released January 1, 1991 by [[Capitol Records]]/[[EMI]], Inc, UPC 077774001335, at [http://www.upcdatabase.com/item.asp?upc=077774001335 UPC Database]; last accessed November 20, 2006.</ref>

Megadeth began their world tour in support of ''So Far, So Good...'' opening for [[Dio (band)|Dio]] in Europe in February 1988, later joining [[Iron Maiden]]'s ''[[Seventh Son of a Seventh Son]]'' summer tour in the US. Noticing problems developing with drummer [[Chuck Behler]], Mustaine brought drummer [[Nick Menza]] in to act as Behler's [[roadie|drum technician]]. As with Gar Samuelson before him, Menza was to be ready to take over for Behler in the event that he could not continue with the tour.<ref>Doreian, Robyn. ''"The Big Four"'', September 1990, ''Hot Metal Magazine'', reported by [http://megadeth.rockmetal.art.pl/articles_hotmetal1990.html The Realms of Deth]; last accessed November 16, 2006.</ref>

In August 1988, Megadeth appeared at the [[Monsters of Rock]] festival at [[Castle Donnington]] in the UK, alongside [[Kiss (band)|Kiss]], [[Iron Maiden]], [[Helloween]], [[Guns N' Roses]], and [[David Lee Roth]], performing to an audience of more than 300,000 people. The band was soon added to the "Monsters of Rock" European tour, but dropped out after the first show. Shortly after that appearance, Mustaine fired both [[Chuck Behler]] and guitarist [[Jeff Young]], and canceled their scheduled 1988 Australian tour. "On the road, things escalated from a small border skirmish into a full-on raging war" he later recalled, "I think a lot of us were inconsistent (on the 1988 tour) because of the guy we were waiting for after the show".<ref>Niles, Eric. ''"Rust in Peace"'', September 1990, ''Music Connection'', reported by [http://megadeth.rockmetal.art.pl/interviews_musicconnection1990.html The Realms of Deth]; last accessed October 13, 2006.</ref>

In July 1989, [[Nick Menza]] was hired to replace Behler on the drums. Unable to find a suitable lead guitarist in time, Megadeth recorded a [[cover version]] of [[Alice Cooper]]'s "No More Mr. Nice Guy" ({{audio| Megadeth-No More Mr Nice Guy.ogg|sample}}) as a three piece band. The version later appeared on the soundtrack to the 1989 [[Wes Craven]] [[Horror film|horror]] movie ''[[Shocker (film)|Shocker]]''. While the band was holding auditions for the new lead guitarist in the summer of 1989, Mustaine was arrested for [[driving while intoxicated]] and possession of narcotics, having crashed into a parked vehicle occupied by an off-duty police officer. He entered court ordered rehab soon after, and got sober for the first time in ten years.<ref name = "MegadethTimeline"/>

===''Rust in Peace'' (1990–1991)===Following Mustaine's new found sobriety, Megadeth began a lengthy search for a new lead guitarist. [[Lee Altus]] of [[Heathen (band)|Heathen]] was among those who auditioned, as was [[Eric Meyer (musician)|Eric Meyer]] of [[Dark Angel (band)|Dark Angel]] fame. Meyer had been invited to join the band following Chris Poland's departure, but had declined in order to remain in Dark Angel.

In 1987, a 16-year-old [[Jeff Loomis]] (of [[Sanctuary (band)|Sanctuary]], and later [[Nevermore]]) auditioned. Afterwards, Mustaine complimented Loomis on his playing, but rejected him because of his age.<ref name="interview1">Metal-Rules.com, ''Nevermore Interview with Jeff Loomis'' at [http://metal-rules.com/interviews/Nevermore-July2003.htm Metal-Rules.com]; last accessed [[April 28]], [[2007]].</ref> Loomis later saw [[Cacophony (band)|Cacophony]] with [[Marty Friedman (guitarist)|Marty Friedman]] and [[Jason Becker]] on tour, and told Friedman, who had just released his first solo effort, ''[[Dragon's Kiss]]'' in 1988, of the experience. Friedman eventually auditioned for the spot, but was initially rejected by Mustaine for having multicolored hair. However, after undergoing what Mustaine called "Rock Star 101," Friedman officially joined Megadeth in February 1990.<ref>Stix, John. ''"A Founding Forefather of Thrash"'', 1990, ''Guitar for the Practicing Musician'', reported by [http://megadeth.rockmetal.art.pl/interviews_practisingmusician1990.html The Realms of Deth]; last accessed October 13, 2006.</ref>

A revitalized Megadeth entered Rumbo Studios in March 1990 with co-producer [[Mike Clink]] to begin work on what would become their most critically acclaimed album to date, ''[[Rust In Peace]]''. For the first time in their career, the band worked sober in the studio, alleviating many of the problems faced recording previous albums. Clink was also the first producer to successfully produce a Megadeth album from start to finish, without being fired.<ref>''"Dave the Human, Mustaine the Artist"'', September 1990, ''Holy Wars... The Punishment Due'' single, reported by [http://megadeth.rockmetal.art.pl/interviews_holywars1990.html The Realms of Deth]; last accessed October 13, 2006.</ref>

Released worldwide on September 24, 1990, ''[[Rust In Peace]]'' was a hit with fans and critics alike, debuting at #23 on the [[Billboard]] Top 200 in the US, and #8 in the UK.<ref>Rock Detector's Official website. ''"Rust in Peace chart positions"'', at [http://web.archive.org/web/20080122144009/http://www.rockdetector.com/discography,5742.sm Rock Detector.com]; last accessed November 16, 2006.</ref> The album showcased a much tighter sound, with Mustaine's writing style adopting a rhythmically complex [[Progressive metal|progressive]] edge, prompting [[Allmusic]] to cite ''Rust in Peace'' as "Megadeth's strongest musical effort".<ref name=autogenerated1>Huey, Steve. ''"Rust In Peace Review"'', ''Allmusic'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:1mzyxdabjola AMG.com]; last accessed November 15, 2006.</ref> The album featured the singles "[[Holy Wars... The Punishment Due]]", ({{audio| Holy Wars clip.ogg|sample}}) and "[[Hangar 18 (song)|Hangar 18]]", ({{audio| Hangar 18 sample clip.ogg |sample}}) both of which received music videos, and remain live staples. ''Rust in Peace'' went on to sell more than a million copies in the US, and received Grammy nominations in 1991 and 1992 for [[Best Metal Performance]].<ref name = "Rock On The Net's list of Best Metal Performance Grammy nominations"/>

In September 1990, Megadeth joined [[Slayer]], [[Testament (band)|Testament]] and [[Suicidal Tendencies]] for the European [[Clash of the Titans (tour)|"Clash of the Titans" tour]], and in October, they were added as the opening band on [[Judas Priest]]'s ''[[Painkiller (Judas Priest album)|Painkiller]]'' tour, culminating with a performance to 140,000 people in January 1991 at [[Rock in Rio#Rock in Rio 2|Rock in Rio 2]] festival in Brazil. Following the success of the European tour, a [[Clash of the Titans (tour)|"Clash of the Titans" US tour]] began in May 1991, featuring Megadeth, [[Slayer]], [[Anthrax (band)|Anthrax]] and opener [[Alice in Chains]]. In July, Megadeth's "Go to Hell" ({{audio| Megadeth Go To Hell sample.ogg|sample}}) was featured on the ''[[Bill & Ted's Bogus Journey]]'' soundtrack, and shortly after "Breakpoint" was featured on the ''[[Super Mario Bros (film)|Super Mario Bros]]'' soundtrack. In 1991, Megadeth also released their first [[home video]], ''[[Rusted Pieces]]'', which contained six of the band's [[music videos]], along with a video interview with the band.

===''Countdown to Extinction'' (1992–1993)===In January 1992, Megadeth entered Enterprise Studios in [[Burbank, California]] with co-producer [[Max Norman]]. Norman, who had mixed ''[[Rust in Peace]]'', would be integral in Megadeth's resulting musical makeover, pushing for shorter, less complicated, and more radio-friendly songs.<ref>Huey, Steve. ''"Countdown To Extinction" AMG review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:4sjb7i3jg72r Allmusic]; last accessed November 20, 2006.</ref> The band spent four months in the studio with Norman, writing and recording what would become Megadeth's most commercially successful effort, ''[[Countdown to Extinction]]''. The album was the first to feature writing contributions from each band member, and was even named by drummer [[Nick Menza]].<ref>Summers, Jodi. ''"Deth Metal!"'', March 1992, ''Metal Hammer'', reported by [http://megadeth.rockmetal.art.pl/articles_metalhammer1992.html The Realms of Deth]; last accessed October 22, 2006.</ref>

On July 14, 1992, Capitol Records released ''[[Countdown to Extinction]]''. The album was an instant hit, debuting at #2 on the Billboard Top 200 album charts in the US, and #5 in the UK.<ref name=BB-A>Billboard's Official website. ''"Megadeth album chart positions"'', at [http://www.billboard.com/bbcom/retrieve_chart_history.do?model.chartFormatGroupName=Albums&model.vnuArtistId=5179&model.vnuAlbumId=646198 Billboard.com]; last accessed November 16, 2006.</ref> Anchored by the [[Mainstream Rock Tracks|Mainstream Rock]] hits "Symphony of Destruction" (#29), {{audio| Symphony of Destruction clip.ogg|sample}} "Foreclosure of a Dream" (#30), and "Sweating Bullets" (#27),<ref name=BB-S>Billboard's Official website. ''"Megadeth singles chart positions"'', at [http://www.billboard.com/bbcom/retrieve_chart_history.do?model.vnuArtistId=5179&model.vnuAlbumId=646198 Billboard.com]; last accessed November 16, 2006.</ref> the album quickly went double platinum in the US, and received a [[Grammy]] nomination for [[Best Metal Performance]] in 1993.<ref name = "Rock On The Net's list of Best Metal Performance Grammy nominations"/>The album's title song, "Countdown to Extinction" also gave Megadeth the distinction of being the only metal band to ever win the "[[Doris Day]] Music Award", presented to the band by the [[Humane Society of the United States]] in 1993 for "spotlighting species destruction and the horrific 'sport' of [[canned hunt]]s".<ref>Humane Society of the United States' Official website. ''"1993 Genesis Awards"'', at [http://web.archive.org/web/20051123171017/http://www.hsus.org/about_us/hsus_hollywood_office/the_genesis_awards/genesis_award_winners_and_memorable_moments/1993_genesis_awards.html HSUS.org]; last accessed October 13, 2006.</ref>

The band released their second [[home video]] ''[[Exposure of a Dream]]'album's title song, in November 1992, continuing in a similar to fashion to ''[[Rusted Pieces]]'', the release featured all music videos previously released from ''Countdown''. Megadeth began their world tour in support of ''"Countdown to Extinction'' in December 1992 with [[Pantera]] and [[Suicidal Tendencies]], followed by a North American tour beginning in January 1993 with [[Stone Temple Pilots]]. Just one month into " also gave Megadeth the North American tour, however, distinction of being the only metal band was forced to cancel all remaining shows, including dates scheduled in Japan, as Mustaine again fell into [[substance abuse]], and ended up in ever win the hospital emergency room.<ref>Chirazi, Steffan. ''"Trial by FireDoris Day Music Award"'', October 1993, ''RIP'', reported presented to the band by [http://megadeth.rockmetal.art.pl/interviews_rip1993.html The Realms the Humane Society of Deth]; last accessed October 13, 2006.</ref> After a seven week stint in rehab, Mustaine emerged clean once again, and the band returned to the studio to record "Angry Again", ({{audio| Angry Again clip.ogg |sample}}) a song which was featured United States in the 1993 film ''[[Last Action Hero]]'', and later nominated for a [[Grammy]] in 1994.<ref name = "Rock On The Netspotlighting species destruction and the horrific 'sport's list of Best Metal Performance Grammy nominationscanned hunts"/>.

In June 1993 Megadeth returned to the stage, appearing as "special guests" at The band released their second home video ''[[MetallicaExposure of a Dream]]'s ', in November 1992, continuing in a similar to fashion to ''[[Milton Keynes BowlRusted Pieces]] Festival'', marking the first time the former bandmates played the same stage in ten years. The pairing prompted Mustainerelease featured all music videos previously released from ''Countdown''s on stage announcement that "The ten years of bullshit is over between Metallica and Megadeth!", although problems would later resurface between the long-feuding bands.<ref name = ROD/> In July, Megadeth was added as the opening act for [[Aerosmith]]began their world tour in support of ''s Countdown to Extinction''in December 1992 with [[Get Pantera]] and Suicidal Tendencies, followed by a Grip Tour|Get A Grip US North American tour]]''beginning in January 1993 with Stone Temple Pilots. Just one month into the North American tour, however, but due the band was forced to contractual disputescancel all remaining shows, including dates scheduled in Japan, as Mustaine again fell into substance abuse, and on stage remarks made by ended up in the hospital emergency room. After a seven week stint in rehab, Mustaine about Aerosmith's emerged clean once again, and the band returned to the studio to record "advancingAngry Again" age, Megadeth a song which was removed from the tour after just seven dates.<ref>Ling, Dave. ''"Get featured in the Van"'1993 film ', January 1998, ''Metal HammerLast Action Hero'', reported by [http://megadeth.rockmetal.art.pl/interviews_metalhammer1998.html The Realms of Deth]; last accessed October 21, 2006and later nominated for a Grammy in 1994.</ref>

Following their canceled US tour, In June 1993 Megadeth returned to the studio to record stage, appearing as "99 Ways to Diespecial guests", ({{audio| 99 Ways To Die.ogg|sample}}) a song that appeared on ''at [[The Beavis and Butt-Head ExperienceMetallica]]'s Milton Keynes Bowl Festival, marking the first time the former band mates played the same stage in ten years. The pairing prompted Mustaine's on stage announcement that "The ten years of bullshit is over between Metallica and Megadeth!", a compilation album featuring songs intercut with commentary by [[Beavis and Buttalthough problems would later resurface between the long-head]]feuding bands. In July, released in November 1993. The song Megadeth was later nominated added as the opening act for a Grammy in 1995 for [[Best Metal Performance]].<ref name = "Rock On The NetAerosmith's ''Get A Grip US tour'', but due to contractual disputes, and on stage remarks made by Mustaine about Aerosmith's list of Best Metal Performance Grammy nominations"/>advancing" age, Megadeth was removed from the tour after just seven dates.

Following their canceled US tour, Megadeth returned to the studio to record "99 Ways to Die", a song that appeared on ''The Beavis and Butt-Head Experience'', a compilation album featuring songs inter cut with commentary by Beavis and Butt-head, released in November 1993. The song was later nominated for a Grammy in 1995 for Best Metal Performance. ===''Youthanasia'' (1994–1995)===Early in 1994, Megadeth again teamed up with co-producer [[Max Norman]] to begin work on the follow up to ''Countdown to Extinction''. With three members of the band now residing in Arizona, initial work began at Phase Four Studios in Phoenix. A few days into pre-production, problems with Phase Four's equipment forced the band to seek out an alternative studio. Mustaine, however, insisted on recording at his home state of Arizona, and no suitable recording facility could be found in time. At the request of co-producer Norman, the band opted to construct their own recording studio inside of a rented [[warehouse]] in [[Phoenix, Arizona]], later dubbed "Fat Planet in Hangar 18".<ref name = "Youthanasia album notes"/> For the first time in their career, the band wrote and arranged the entire album in studio, and included basic tracks recorded live by the whole band at the same time.<ref name = "Parader1995"/>

Following eight months in the studio, ''[[Youthanasia]]'' was released on November 1, 1994, debuting at #4 on the [[Billboard]] Top 200 album chart in the US.<ref name=BB-A /> The album was certified gold in Canada in just thirty minutes, and was certified platinum in the US faster than any other Megadeth album. With producer Max Norman still pushing for a slower, more commercial sound, ''Youthanasia'' followed the stylistic shift that began with ''Countdown to Extinction''.<ref>Erlewine, Stephen Thomas. ''"Youthanasia" AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:itouaknkhm3z AMG.com]; last accessed November 16, 2006.</ref> While still retaining core metal elements, the album focused on stronger vocal melodies and more accessible, radio friendly arrangements.<ref name=AMGY>Birchmeier, Jason. ''"Youthanasia" Remastered version AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:06xsa9tge23u AMG.com]; last accessed November 16, 2006.</ref> The band even enlisted noted fashion photographer Richard Avedon to further their new image, dropping their jeans and t-shirts for a more style conscious look.<ref name="Parader1995">Merkle, P.J. ''"Megadeth: Bewitched, Bothered and Bewildered"'', May 1995, ''Hit Parader'', reported by [http://megadeth.rockmetal.art.pl/interviews_hitparader1995.html The Realms of Deth]; last accessed October 22, 2006.</ref>

A sticker on initial releases of ''[[Youthanasia]]'' advertised the then-new concept of a band [[website]], affectionately known as "Megadeth, Arizona". Fans could chat in the "Mega-diner", correspond with the band through email, request songs to be played live, and read columns and tour diaries written by band members.<ref name = "Eleven1995"/>

''Youthanasia's'' first single, "Train of Consequences",({{audio| Train of Consequences.ogg|sample}}) reached #29 on Billboard's Mainstream Rock charts, and in November 1994, Megadeth appeared on the ''[[Late Show with David Letterman]]'', performing the album's second single, "[[A Tout le Monde|À Tout Le Monde]]". ({{audio| A Tout Le Monde.ogg|sample}})<ref name="Eleven1995">Boerio, Jeff. ''"Megadeth: Online and Onstage"'', 1995, ''On Eleven Magazine'', reported by [http://megadeth.rockmetal.art.pl/interviews_eleven1995.html The Realms of Deth]; last accessed October 22, 2006.</ref> "[[A Tout le Monde|À Tout Le Monde]]" also received a music video, which [[MTV]] refused to play, thinking its lyrics were an endorsement of [[suicide]].<ref name = "Youthanasia album notes"/>Apparently playing videos of hip hop thugs stuttering about drugs, thug life, murder and flashing gang signs is better to MTV.

Live support for ''Youthanasia'' began in South America in November 1994, and would span eleven months, becoming Megadeth's most extensive tour to date. The band was joined by [[Corrosion of Conformity]] in both Europe and the US, and [[Flotsam and Jetsam (band)|Flotsam and Jetsam]], [[Korn]] and [[Fear Factory]] in the US. The tour culminated with an appearance at the ''[[Monsters of Rock]]'' festival in Brazil, co-headlining alongside [[Alice Cooper]] and [[Ozzy Osbourne]]. In January 1995, Megadeth appeared on the soundtrack to the horror film ''[[Demon Knight|Tales from the Crypt Presents: Demon Knight]]'' with the song "Diadems". Megadeth also contributed a cover version of "Paranoid" ({{audio| Paranoid clip.ogg |sample}}) to ''[[Nativity in Black]]'', the first [[Black Sabbath]] tribute album. The band's version of "Paranoid" was nominated for a Grammy in 1996 for [[Best Metal Performance]], Megadeth's sixth nomination in as many years.<ref name = "Rock On The Net's list of Best Metal Performance Grammy nominations"/>

In March 1995, Megadeth released a special edition of ''Youthanasia'' in Europe, containing a bonus disc entitled ''[[Hidden Treasures]]''. The bonus disc featured every one-off song by Megadeth, from film soundtracks, compilations, and tribute albums, including a new recording of the [[Sex Pistols]]' "Problems". Due to fan demand, the bonus disc was released as its own [[Extended play|EP]] in the United States and Japan in July 1995.

===''Cryptic Writings'' (1996–1998)===Following an extensive world tour in support of ''Youthanasia'', Megadeth took time off late in 1995. Mustaine began work on [[MD.45]], a side project with vocalist [[Lee Ving]] of [[Fear (band)|Fear]]. The band underwent changes on the business side, signing with ESP Management, and hired a new "creative manager" Bud Prager, a previous manager of both [[Foreigner (band)|Foreigner]] and [[Bad Company]].<ref>Nalbandian, Bob. ''"David Ellefson & Marty Friedman Interview"'', 1998, ''Hard Radio.com's Shockwaves'', reported by [http://web.archive.org/web/20020124023314/http://www.hardradio.com/shockwaves/megadeth1.html Hard Radio.com]; last accessed November 16, 2006.</ref> As with Max Norman before him, Prager would go on to be highly influential in shaping the direction of the band. He pushed Megadeth further into the "commercial rock" field, and convinced the band to work with Nashville pop producer and former [[Giant (band)|Giant]] guitarist [[Dann Huff]].<ref name = "Cryptic Writings album notes"/>

In September 1996, Megadeth began working on songs for their next album in Nashville, tentatively titled ''Needles and Pins''. The writing process was closely supervised by new manager Bud Prager, who also contributed musical ideas and lyrics to the songs. Many lyrics, and even song titles were changed at the request of Prager. Regarding Prager's writing influence, Mustaine later wrote "I figured maybe this guy (Prager) could help me get that intangible 'Number One' record I so badly wanted"<ref name = "Cryptic Writings album notes"/> Due to a problem with the album's original artwork, the album cover was replaced with a "voodoo symbol", and renamed ''[[Cryptic Writings]]''.

On June 17, 1997, [[Capitol Records]] released ''[[Cryptic Writings]]''. The album debuted at #10 on the Billboard Top 200,<ref name=BB-A /> and was Megadeth's sixth consecutive studio album to be certified gold in the United States.<ref name=Blabber>Blabbermouth.net Official website. ''"Megadeth - Album Sales Update"'', at [http://www.roadrunnerrecords.com/blabbermouth.net/news.aspx?mode=Article&newsitemID=45667 Blabbermouth.net]; last accessed November 16, 2006.</ref> ''Cryptic Writings'' scored Megadeth their highest charting single to date, the #5 [[Mainstream Rock Tracks|Mainstream Rock Track]], "[[Trust (Megadeth song)|Trust]]", ({{audio| Trust.ogg|sample}}) which was also nominated for a [[Best Metal Performance]] [[Grammy]] in 1998.<ref name = "Rock On The Net's list of Best Metal Performance Grammy nominations"/> Press response to the album was mixed,<ref>Wiederhorn, Jon. ''"Cryptic Writings" Rolling Stone Review'', at [http://www.rollingstone.com/artists/megadeth/albums/album/258853/review/5946247/cryptic_writings Rolling Stone.com]; last accessed November 16, 2006.</ref><ref>Erlewine, Stephen Thomas. ''"Cryptic Writings" AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:ybaxlfwehcqr AMG.com]; last accessed November 16, 2006.</ref><ref>Birchmeier, Jason. ''"Cryptic Writings" Remastered version AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:1gjyeaz74xu7 AMG.com]; last accessed November 16, 2006.</ref> but the album would go on to score four top 20 [[Mainstream Rock Chart|Mainstream Rock Tracks]], including "[[Almost Honest (Megadeth song)|Almost Honest]]" (#8), "[[Use the Man]]" (#15), and "[[A Secret Place (Megadeth song)|A Secret Place]]" (#19) {{audio| A Secret Place.ogg|sample}}.<ref name=BB-S />When asked about the eclectic nature of the album, Mustaine later said "We divided it into thirds. One part of the record was really fast and aggressive, one third of it was the really melodic, in between stuff, and then the final third was really radio-orientated music like ''Youthanasia''".<ref name="GW1998">Wiederhorn, Jon. ''"Last Men Standing"'', June 1998, ''Guitar World'', reported by [http://megadeth.rockmetal.art.pl/interviews_guitarworld1998.html The Realms of Deth]; last accessed October 13, 2006.</ref>

After more than a year away from When asked about the eclectic nature of the stagealbum, Megadeth returned as a live act in June 1997, beginning a world tour with [[Misfits (band)|The Misfits]], and Mustaine later touring in said "We divided it into thirds. One part of the United States with [[Life of Agony]] record was really fast and [[Coal Chamber]]. In July Megadeth joined [[Ozzfest|Ozzfest 98]]aggressive, but halfway through one third of it was the tourreally melodic, drummer Nick Menza discovered a tumor on his kneein between stuff, and was forced to leave then the tour to undergo surgery. He final third was replaced by [[Jimmy DeGrasso]], temporarily at first. Following the tour, however, DeGrasso replaced Menza permanently, after Mustaine claimed that Menza had "lied about having cancer".<ref>Ferres, Nick. really radio-orientated music like ''"An Ugly American"Youthanasia'', March 2001, ''Rockmetal.pl'', reported by [http://megadeth.rockmetal.art.pl/interviews_rockmetal2001.html The Realms of Deth]; last accessed November 16, 2006".</ref>

In 1998After more than a year away from the stage, Megadeth returned as a live act in June 1997, beginning a world tour with The Misfits, and later touring in the United States with [[computer gameLife of Agony]] development company and [[3D RealmsCoal Chamber]] announced that they would be using two unreleased . In July Megadeth tracks on their promotional album ''joined [[Duke Nukem (character)Ozzfest|Duke NukemOzzfest 98]]: Music to Score By''. First was a rendition of , but halfway through the Duke Nukem theme song "Grabbag"tour, originally composed by Lee Jacksondrummer Nick Menza discovered a tumor on his knee, and second was a Megadeth song originally recorded in 1995, "New World Order", which later appeared on forced to leave the remastered edition of ''[[Youthanasia]]''tour to undergo surgery.<ref>[http://wwwHe was replaced by Jimmy DeGrasso, temporarily at first.3drealms.com/news/1999/08/duke_nukem_musi.html Duke Nukem: Music to Score By]; [[3D Realms]]Following the tour, August 9however, 1999; last accessed 12 MarchDeGrasso replaced Menza permanently, 2009after Mustaine claimed that Menza had "lied about having cancer".</ref>

In 1998, computer game development company 3D Realms announced that they would be using two unreleased Megadeth tracks on their promotional album ''Duke Nukem: Music to Score By''. First was a rendition of the Duke Nukem theme song "Grabbag", originally composed by Lee Jackson, and second was a Megadeth song originally recorded in 1995, "New World Order", which later appeared on the remastered edition of ''[[Youthanasia]]''.===''Risk'' (1999–2000)===Following the band's first real radio success with ''Cryptic Writings'', Megadeth opted to again work with [[country pop]] producer [[Dann Huff]] in [[Nashville, Tennessee|Nashville]] on their eighth studio album, which began in January 1999. The writing of the album was again supervised by manager Bud Prager, credited with co-writing on five of the album's twelve songs.<ref>''"Risk"'' album notes''. August 31, 1999, [[Capitol Records]], 7243-4-99134-0-0.</ref> Prager convinced Mustaine to grant producer Dan Huff more control over the recording process. "When it comes to Risk," Mustaine later wrote, "there'd been people in there playing and I wouldn't even know who they were or where the parts came from, and I'm not used to that. I was a little bit intimidated by the success we had with ''Cryptic Writings'', so when it came to creating new material after that, it's like being "power-drunk" - you want more. After the success with "Trust", I thought to myself "wow, we've had a number one hit". We'd had four top five hits in a row, so why would I not want to give Dan even more control when it comes to the producing part on the next record? So I did, and it backfired".<ref>Hjelm, Fredrik. ''"It Wasn't Fun Anymore"'', 2001, ''Shockwaves Online'', reported by [http://megadeth.rockmetal.art.pl/interviews_shockwaves2001.html The Realms of Deth]; last accessed October 21, 2006.</ref>

Released on August 31, 1999, ''[[Risk (album)|Risk]]'' was both a critical and commercial failure, and led to a backlash from many longtime fans.<ref name=AMGRisk>Birchmeier, Jason. ''"Risk" Remastered version AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:jgjueaz74xh7 AMG.com]; last accessed November 16, 2006.</ref><ref name = MR/><ref>Billerey-Mosier, Roger. ''"Risk" Album Review'', September 1999, at [http://web.archive.org/web/20071224081817/http://www.ssmt-reviews.com/db/searchrev.php?artistID=720&showReview=true#R1657 ssmt-reviews.com]; last accessed November 16, 2006.</ref> Although recent Megadeth albums had incorporated mainstream rock elements alongside a more traditional heavy metal sound, ''Risk'' was virtually devoid of metal, featuring instead dance, [[electronica]], and [[disco]] influences.<ref name=AMGRisk /> ''Risk'' was Megadeth's first release since 1985 not to be certified gold or higher in the US.<ref name=Blabber /> The album's lead-off single, "Crush Em", ({{audio| Crush Em.ogg|sample}}) appeared on the ''[[Universal Soldier: The Return]]'' soundtrack, temporarily as [[World Championship Wrestling]]'s entrance theme for [[Bill Goldberg]] and later became an official [[NHL]] song, played during hockey games.<ref name=MR>Music-Reviewer.com. ''"Risk" Album Review'', November 1999, at [http://www.music-reviewer.com/11_99/newrel25i.htm Music-Reviewer.com]; last accessed November 16, 2006.</ref> Singles were made out of [[Crush 'Em]], [[Breadline (song)| Breadline]] and [[Insomnia (Megadeth song)|Insomnia]].

In July 1999, Megadeth recorded a cover version of the [[Black Sabbath]] song "[[Never Say Die (song)|Never Say Die]]", which appeared on the second [[Nativity in Black]] tribute album.They began their world tour in support of ''Risk'' in September 1999, playing alongside [[Iron Maiden]] during the European leg. Three months into the tour, longtime guitarist [[Marty Friedman (guitarist)|Marty Friedman]] announced that he would be leaving the band,<ref name = "MegadethTimeline"/> citing musical differences. As Mustaine later explained: "I told (Marty) after ''Risk'' that we had to go back to our roots and play metal, and he quit".<ref name=BM2>Blabbermouth.net. ''"Dave Mustaine Slams Former Bandmates, Defends His Current 'Boys' "'', at [http://www.roadrunnerrecords.com/blabbermouth.net/news.aspx?mode=Article&newsitemID=33201 Blabbermouth.net]; last accessed November 16, 2006.</ref> Megadeth enlisted guitarist [[Al Pitrelli]], formerly of [[Savatage]], [[Alice Cooper]], and currently of [[Trans-Siberian Orchestra]], as Friedman's replacement in January 2000.<ref name = "MegadethTimeline"/>

Megadeth returned to the studio in April 2000, to begin work on their ninth studio release. However, one month into production the band was given the opportunity to join the "Maximum Rock" tour, alongside [[Anthrax (band)|Anthrax]] and [[Mötley Crüe]]. Megadeth put the recording on hold, and toured North America throughout the summer of 2000.<ref name = "MegadethTimeline"/> Early into the tour, Anthrax dropped off the bill, allowing Megadeth to play an extended, co-headlining set.

Megadeth and [[Capitol Records]] parted ways in October 2000, after fourteen years. The label returned the band's newest recordings, and in return released a [[greatest hits]] record, ''[[Capitol Punishment: The Megadeth Years]]''. The album also featured two new tracks, "Kill the King", and "Dread and the Fugitive Mind", ({{audio| Dread And The Fugitive Mind.ogg|sample}}) both of which showcased the band's return to their metal roots following ''Risk''.

===''The World Needs a Hero'' (2001–2002)===In November 2000, Megadeth signed with new label [[Sanctuary Records]]. The band returned to the studio in October to put the finishing touches on their next album, which had been near completion before the band joined the "Maximum Rock" tour six months earlier. Following the overwhelming negative response to ''Risk'',<ref name=AMGW>Huey, Steve. ''"The World Needs A Hero" AMG review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:vt8m96hojepo Allmusic]; last accessed November 20, 2006.</ref> Mustaine fired manager Bud Prager, and decided to self-produce Megadeth's next album. ''[[The World Needs a Hero]]'', the first Megadeth album since ''Peace Sells... but Who's Buying?'' to be written entirely by Mustaine (with one contribution from Al Pitrelli on "Promises"), was released on May 15, 2001 to mixed reviews.<ref name=AMGW /><ref>Engels, John. ''"The World Needs A Hero" Review'', June 14, 2001, at [http://www.orlandoweekly.com/music/review.asp?rid=2359 OrlandoWeekly]; last accessed November 19, 2006.</ref> While the album marked a return to form following the attempted mainstream rock direction featured on ''Risk'', some critics felt the album fell short of expectations.<ref>Eldefors, Vincent. ''"The World Needs A Hero" Review'', 2001, at [http://www.tartareandesire.com/reviews/megadeth_hero.html Tartarean Desire.com]; last accessed November 19, 2006.</ref><ref>Chandrasekhar, Chaitra. ''"The World Needs A Hero" Review'', Published In "The Tech" newspaper on May 15, 2001, Volume 121, Number 26, archived at [http://tech.mit.edu/V121/N26/Megadeth.26a.html The Tech official site]; last accessed November 19, 2006.</ref> [[Image:Megadeth2001.jpg|thumb|right|200px|Megadeth, 2000-02 (L-R) Pitrelli, DeGrasso, Ellefson, Mustaine. Final line-up before breakup.]] Mustaine himself likened the album to be the first major turn of a huge ship at sea, trying to right itself and get back on course. The album's lead off single, "[[Moto Psycho]]", ({{audio| Motopsycho.ogg|sample}}) reached #22 on the Billboard Mainstream Rock charts,<ref name=BB-S /> also receiving regular airplay on [[VH1]]'s ''Rock Show''.

Touring in support of ''The World Needs a Hero'' began in the summer of 2001 in Europe supporting [[AC/DC]], followed by an American tour with [[Iced Earth]] and [[Endo (band)|Endo]] in September. The tour was cut short however, following the attacks on America on [[September 11, 2001 attacks|September 11]], the band were forced to cancel all scheduled dates, including a DVD shoot set in [[Argentina]]. Although they did perform one show at the Commador Ballroom in Vancouver, B.C. on September 12. Instead the band played two shows in Arizona in November, which were filmed and later released as ''[[Rude Awakening (Megadeth album)|Rude Awakening]]'', Megadeth's first official live release. The DVD went gold on July 23, 2002. In February 2002, Mustaine remixed and remastered Megadeth's first album, ''[[Killing Is My Business... and Business Is Good!]]'', with modern mixing and mastering techniques used on modern metal albums, and added bonus tracks.<ref name="MegadethTimeline">Megadeth's Official website, ''"Timeline"'', 2006, at [http://web.archive.org/web/20070506213407/http://www.megadeth.com/index.php?section=history Megadeth.com]; last accessed October 11, 2006.</ref>

===Breakup (2002–2004)===In January 2002, Mustaine was admitted to the hospital to remove a [[kidney stone]]. While undergoing treatment, he was administered pain medication, which triggered a relapse. Following his hospital stay, he immediately checked himself into a treatment center in Texas.<ref name = "GW2003"/> While at the treatment center, Mustaine suffered a freak injury causing severe nerve damage to his left arm. The injury, induced by falling asleep with his left arm over the back of a chair, caused compression of the [[radial nerve]]. He was diagnosed with [[radial neuropathy]], which left him unable to grasp or even make a fist with his left hand (a condition known as Saturday Night Palsy).<ref name = "Megadeth Disbands Press Release"/>

On April 3, 2002, Mustaine announced in a press release that he was disbanding Megadeth, officially due to his arm injury.<ref name="Megadeth Disbands Press Release">Megadeth's Official website, ''"Megadeth Disbands Press Release"'', 2006, at [http://www.megadeth.com/news/pr/disband.html]; last accessed November 15, 2006.</ref> For the next four months, Mustaine underwent intense [[physical therapy]] five days a week.<ref name="GW2003">Epstein, Dan. ''"Die Another Day"'', August 2003, ''Guitar World'', reported by [http://megadeth.rockmetal.art.pl/interviews_guitarworld2003.html The Realms of Deth]; last accessed October 21, 2006.</ref> Slowly, Mustaine began to play again, but was forced to "re-teach" his left hand.

In order to fulfill contract obligations with [[Sanctuary Records]], Megadeth released a compilation album, ''[[Still Alive... and Well?]]'' on September 10, 2002. The first half of the album contains live tracks recorded at the Web Theatre in [[Phoenix, Arizona]], on November 17, 2001. The second half of the album contains studio recordings taken from ''The World Needs a Hero''.

Following nearly a year of recovery, including physical and [[electric shock]] therapy,<ref name = MetalTemple/> Mustaine began work on what was to be his first solo album. The new material was recorded with session musicians [[Vinnie Colaiuta]] and [[Jimmy Sloas]] in October 2003, but the project was put on hold when Mustaine agreed to remix and remaster Megadeth's [[Megadeth discography#Studio albums|eight album back catalog]] with [[Capitol Records]]. Mustaine re-recorded some parts that were lost over time, or altered without his knowledge in the initial mixing process.

===''The System Has Failed'' (2004–2005)===In May 2004 Mustaine returned to his newest recordings, intended as a solo effort, but due to outstanding contractual obligations with the band's European label [[EMI]], he was forced to release one more album under the "Megadeth" name.<ref name=HardRadio>Nalbandian, Bob. ''"Dave Mustaine Interview"'', August 28, 2004, ''Hard Radio.com'', reported by [http://www.hardradio.com/shockwaves/mustaine6.php3 Hard Radio.com]; last accessed November 19, 2006.</ref> Mustaine decided to reform the band, and contacted the fan favorite "Rust in Peace line-up" to re-record backing tracks on his latest songs. While drummer Nick Menza initially signed on, Marty Friedman and David Ellefson were both unable to come to an agreement with Mustaine.<ref name=autogenerated2>Nalbandian, Bob. ''"Dave Mustaine Interview"'', August 28, 2004, ''Hard Radio.com'', reported by [http://www.hardradio.com/shockwaves/mustaine2.php3 Hard Radio.com]; last accessed November 19, 2006.</ref> Regarding longtime bassist Ellefson not returning to the band, Mustaine said: "David lied to me in the press, he said that my arm injury was fake, went around town and slandered me. We made him a really good offer (to rejoin the band) and he said no. I mean, if I give you an offer and you don't take it, it means no, right?"<ref name=MetalTemple> ''"Interview with Dave Mustaine of Megadeth"'', July 20, 2004, ''Metal-Temple.com'', reported by [http://www.metal-temple.com/interview.asp?id=94 Metal Temple.com]; last accessed November 19, 2006.</ref> The new album would be the first ever Megadeth recording not to feature Ellefson. Original lead guitarist [[Chris Poland]] (from the 'Killing is My Business' and 'Peace Sells' era) was hired by Mustaine to contribute guitar solos to the new album; the first time the two musicians had worked together since Poland's dismissal from the band in the 1980s. Poland opted to serve as a studio musician only, as he wished to remain focused on his own [[jazz fusion]] project OHM.

On September 14, 2004 Megadeth released their comeback album, ''[[The System Has Failed]]'' on [[Sanctuary Records]] in the US and [[EMI]] in Europe. Heralded as a return to form,<ref name=AMGS>Birchmeier, Jason. ''"The System Has Failed" AMG Review'', at [http://www.allmusic.com/cg/amg.dll?p=amg&sql=10:emf5zfg4ehak Allmusic]; last accessed November 19, 2006.</ref> ''[[Revolver (magazine)|Revolver]]'' magazine gave the album four stars, calling ''The System Has Failed'' "Megadeth's most vengeful, poignant and musically complex offering since ''[[Countdown to Extinction]]''".<ref>Megadeth's Official website press release ''"Megadeth: Announce dates for "BLACKMAIL THE UNIVERSE TOUR" and band line-up as new CD ‘THE SYSTEM HAS FAILED' hits stores"'', September, 2004, reported by [http://www.megadeth.com/news/pr/releasetour.html Megadeth.com]; last accessed November 19, 2006.</ref> The album debuted on the ''Billboard'' 200 chart at #18,<ref name=BB-A /> and was led by the radio single "Die Dead Enough", ({{audio| Die Dead Enough.ogg|sample}}) which reached #21 on the US Mainstream Rock charts.<ref name=BB-S /> Mustaine announced that the album would be the band's last, followed by a farewell tour, after which he would focus on a solo career.[[Image:Megadeth at Sauna crop.jpg|thumb|left|200px|Megadeth (June 2005) 2004-06 line-up. (l-r) Shawn Drover, MacDonough, Mustaine, Glen Drover]]

Megadeth began the ''Blackmail the Universe'' world tour in October 2004, enlisting touring bassist [[James MacDonough]] ([[Iced Earth]]), and guitarist [[Glen Drover]] ([[Eidolon (band)|Eidolon]], [[King Diamond]]). While in rehearsal for the tour, newly returned drummer [[Nick Menza]] once again parted ways with the band, as he was unable to prepare for the physical demands of a full US tour.<ref>Brave Words.com ''"MEGADETH Tour Manager Talks About Drummer Nick Menza's Departure"'', November 5, 2004, reported by [http://www.bravewords.com/news/19670 Brave Words.com]; last accessed November 19, 2006.</ref> He was replaced just five days before the first show by [[Shawn Drover]] ([[Eidolon (band)|Eidolon]]), brother to new guitarist Glen Drover, and also a member of the Canadian [[thrash metal]] band [[Eidolon (band)|Eidolon]]. The band toured the US with [[Exodus (band)|Exodus]], and later in Europe with [[Diamond Head (band)|Diamond Head]] and [[Dungeon (band)|Dungeon]].<ref name = "MegadethTimeline"/>