A subset of Heavy Metal which combines the musical intricacies of Progressive Rock with the heavy, guitar/drum-driven sound of metal. Progressive Metal may also include more overt flavorings of Classical music, such as operatic vocals or symphonic arrangements; bands with modern classical leanings usually skew more towards Avant-Garde Metal. As with other forms of metal, the lyrical themes tend to be Darker and Edgier compared to traditional prog, with more sophistication than other forms of hard rock. A concrete definition of progressive metal is hard to pin down, so the status of many bands as progressive metal can be ambiguous. Its roots trace all the way back to hard rock and early heavy metal acts who dabbled in progressive rock (namely Led Zeppelin, Black Sabbath, Deep Purple, Rainbow, and Scorpionsnote ), as well as prog acts with heavier songs (particularly King Crimson, Rush and Hawkwind), and Mercyful Fate and Iron Maiden were among the first acts to play traditional heavy metal with overt prog elements. Progressive metal itself is generally agreed to have solidified with Queensrÿche, Watchtower, Crimson Glory, Fates Warning, and Voivod, while Savatage's burgeoning Rock Opera-centric Signature Style and heavily showtune-influenced compositions also helped build the genre, though it is debatable whether they were a full example by the time that the others were making their mark.
It helps that there's been an overlap between both metal and prog from the beginning since both genres were in heavy rotation on FM rock stations in America in the early '70s.
Also, see Technical Death Metal, Avant-Garde Metal and the "Avant-Garde/Progressive Black Metal" section in the Black Metal article. Another notable subgenre is Neo Classical Metal, also known as 'Guitar Virtuoso Music'. This is basically heavy metal with an electric guitar playing classical music instead of rock, and it often overlaps with either Speed Metal, Power Metal, or Glam Metal.
Notable Progressive Metal bands include:
- Abstrakt Algebra (overlaps with Doom Metal and Power Metal)
- Adagio (also Power Metal, later material has some djent elements)
- Agalloch (overlaps with Doom Metal, Black Metal, and Folk Metal)
- Aghora (often called "Jazz Metal")
- Aina
- Akercocke (also classed as progressive Black Metal, Progressive Death Metal, blackened death metal, and probably a number of other things)
- Alarum (mixed with Death Metal)
- Alchemist
- The Algorithm (mixed with Electronic Dance Music)
- Alkaloid (mixed with Death Metal, also some avant-garde elements)
- Allegaeon (Damnum, also Technical Death Metal, though they had been moving in this direction since Proponent for Sentience)
- Alter Bridge (Creed minus Scott Stapp = this)
- Amniote
- Amorphis (First album was straight-up Death Metal, and their second album was Melodeath/Doom Metal. However, from their third album on, they've been prog metal)
- Anciients
- Angra (also Power Metal and Symphonic Metal)
- Animals as Leaders
- [ANTI]faith
- Architects (mixed with Metalcore)
- Arcturus (mixed with Black Metal on the early recordings, but this is reduced starting with La Masquerade infernale)
- Area 11
- Arkaik (circa Metamorphignition)
- Atheist (also the trope codifiers for Technical Death Metal)
- Augury (along with Death Metal)
- August Burns Red (mixed with Metalcore)
- Avenged Sevenfold have some minor progressive elements in most of their albums, but dived headfirst into it with The Stage.
- The Stage (2016)
- Ayreon
- 2016 - The Theater Equation
- Baroness
- Battle Of Mice
- Between the Buried and Me (mixed with Metalcore and Death Metal)
- Beyond Creation (also Technical Death Metal)
- Black Crown Initiate (mixed with Death Metal, as well as djent on The Song of the Crippled Bull)
- Black Fast (mixed with thrash and death metal)
- Blind Illusion (mixed with Thrash Metal, also noteworthy as the band where Les Claypool and Larry LaLonde first played together)
- Blood Incantation (progressive death metal on Hidden History of the Human Race, though they had flirted with prog on Starspawn)
- Blut aus Nord (mixed with Black Metal and Industrial Metal starting with The Mystical Beast of Rebellion)
- Borknagar (later material mixed this with Viking Metal, early material was straight-up Black/Viking Metal)
- Caligula's Horse
- Candiria (also Jazz Fusion and Rap Metal)
- Cattle Decapitation (also Death Metal)
- Cellar Darling
- The Chasm (also Death Metal)
- Chaotrope (Electronic Metal)
- Circle Takes the Square (vaguely; also falls under Screamo Music, Post-Hardcore, Post-Rock, and numerous other genres. The "progressive" part isn't really debatable; Prog Archives has them listed as a Tech/Extreme Prog Metal band, for what that's worth)
- Circus Maximus
- Coheed and Cambria (also falls under Alternative Rock, Post-Hardcore, and Alternative Metal, with slight Pop Punk influences as well; a strange combo, to say the least)
- Conception
- Cormorant (also takes influences from Melodic Death Metal, Black Metal, Folk Metal and Hard Rock)
- The Contortionist (originally djent, gradually downplayed this with each album)
- Crimson Glory (also Power Metal)
- Cult of Luna (progressive sludge metal)
- Cynic (earliest material is more Death Metal-oriented; modern material is more rock-oriented)
- D
- The Dali Thundering Concept (also Deathcore)
- Dark Angel (mixed with Thrash Metal, mostly on their last two albums, especially the last one)
- Dark Fortress (mixed with Melodic Black Metal)
- Dark Matter Secret (instrumental progressive/technical death metal)
- Darkwater
- Dawnbringer
- Death (the first Death Metal band, who gradually moved towards prog metal the further along they went with the band. By their last album, The Sound of Perseverance, they were most definitely a prog metal band. Schuldiner's next project, Control Denied, delved even further into prog, while reducing the Death Metal influence to almost nil and replacing it with mild Power Metal influence instead.)
- Deathspell Omega (mixed with Black Metal and Avant-Garde Metal)
- The Furnaces of Palingenesia (2019)
- Decrepit Birth (had elements of this on Diminishing Between Worlds, but Polarity is where it became really prominent)
- Defeated Sanity (Dharmata EP, mixed with Technical Death Metal)
- Diablo Swing Orchestra (Also Avant Garde Metal, Swing, salsa... well they cover a wide range of styles in a single song)
- Dir en grey (their music is such an extreme example of Genre-Busting that there are often multi-page arguments over what exact genre they belong to, but many of their songs, such as "Vinushka", "Macabre", and "Diabolos", unambiguously qualify as progressive metal)
- Disarmonia Mundi (also Melodic Death Metal)
- Divine Disorder (Which overlaps with Orchestral, Symphonic & Death Metal)
- Dorso
- Dream Theater (probably the Trope Codifiers for the genre as a whole)
- 1992 - Images and Words
- 1999 - Metropolis Pt. 2: Scenes from a Memory
- 2016 - The Astonishing
- DVSR (an unusual Rap Metal example)
- East Of The Wall (a bit of this, a bit of Post-Rock)
- Edge of Sanity (also Melodic Death Metal)
- An Endless Sporadic
- Enslaved (also Black Metal; prog influence is much stronger in recent material than early material, although it was always evident on most of their albums)
- Entheos (Dark Future)
- Ephel Duath (mixed with Black Metal, jazz, and a wide variety of other disparate genres)
- Epica, one part progressive metal, one part Symphonic Metal.
- Erra (fused with Metalcore)
- Evergrey (also Power Metal; notable for being one of the only bands in the genre to avert Epic Rocking most of the time)
- Exivious (mixed with jazz fusion)
- Extol (with Death Metal, Black Metal, or Thrash Metal fused in depending on the album)
- Exotype (Genre-Busting example combined with Metalcore, Nu Metal, Deathcore, Djent, Brostep, Industrial, Glitch, Trance, and whatever else they feel like)
- The Faceless (Autotheism, along with death metal)
- Faith No More (also Funk Metal and Alternative Metal)
- Fair to Midland (also Progressive Rock, Alternative Metal, Folk Metal)
- Fallujah (The Harvest Wombs onwards)
- Fates Warning (Trope Codifier; their output with John Arch overlaps with Power Metal)
- Fen (mixed with Black Metal and post-metal)
- Finsterforst (mixed with Folk Metal and a bit of Black Metal)
- Fireaxe
- 2003 - Food for the Gods
- Forbidden (mixed with Thrash Metal on Twisted into Form and Groove Metal on Distortion and Green)
- Freak Kitchen (overlaps with Hard Rock and Avant-Garde Metal)
- Furyu
- Galactic Cowboys
- GaMetal (A project based around Progressive Metal remixes of songs from Video Games)
- The Gathering
- Genghis Tron
- Gigan
- Gojira (mixed with Death Metal and Groove Metal)
- Gorod (A Perfect Absolution, mixed with Melodic Death Metal)
- Gospel of the Witches (a Genre-Busting example like Ephel Duath, its spiritual predecessor, but definitely closer to prog than to the Avant-Garde Metal leanings of the latter)
- Green Carnation
- Hacktivist (Overlaps with Djent, and is quite possibly the only band that can fall into this and Rap Metal)
- Hammers of Misfortune (Genre-Busting example that mixes elements of this, traditional doom metal, folk metal, and traditional heavy metal, among various other things)
- Hannes Grossmann (along with Death Metal; yes, it's a solo project)
- Haji's Kitchen (also Groove Metal and Grunge)
- Haken
- Hexenhaus (also Power Metal and Thrash Metal)
- Horrendous (Ecdysis and Idol, also death metal)
- I built the sky
- Inanimate Existence (A Never-Ending Cycle of Atonement onward, mixed with Technical Death Metal)
- Inter Arma (a Genre-Busting example that is equal parts this, post-metal, sludge metal, and Black Metal)
- Interloper
- Intronaut (combined with post-metal)
- Iron Maiden (many of their epics such as "Hallowed Be Thy Name" and "Rime of the Ancient Mariner" qualify as arguable Ur-Examples as does the album Seventh Son of a Seventh Son. In modern times, they are unabashedly prog, with three songs on The Book of Souls stretching well past the ten-minute mark and the longest being just over eighteen)
- Irreversible Mechanism (mixed with Death Metal)
- Isis (also Trope Codifier for post-metal)
- Karnivool, particularly their sophomore album, 'Sound Awake'. The band has stated they try to reinvent themselves each time they go into the studio to record.
- Kayo Dot (mixed with Avant-Garde Music and a wide variety of other disparate influences)
- King Crimson (their heavier output in the 70's was a noticeable Ur-Example of the genre, which they fully embraced in the late 90's)
- King's X (Also Alternative Metal, Funk Metal, and Hard Rock)
- Krallice (mixed with Black Metal)
- Krux (also Doom Metal)
- Lascaille's Shroud
- Last Chance To Reason
- Leprous (earlier material; they started to downplay the metal elements on The Congregation and abandoned every last pretense of being a metal act on Pitfalls)
- Liquid Tension Experiment
- Jeff Loomis (less so than some of his other projects, but still mixes in a lot of this in his solo material)
- Arjen Anthony Lucassen
- 1995-2013 - Ayreon
- 2012 - Lost in the New Real
- Make Them Suffer (overlaps with Deathcore)
- Mastodon (mixed with Sludge Metal on the early recordings, but this has lessened with time)
- maudlin of the Well (mixed with Avant-Garde Metal, Death Metal, and a wide variety of other influences)
- Megadeth (although they are mostly a straight-up Thrash Metal or Heavy Metal band, Rust in Peace is one of the most noteworthy and acclaimed examples of progressive thrash metal)
- Mekong Delta (The Music of Erich Zann onwards, though they had some basic elements of this on their debut)
- Memento Mori (overlaps with Power Metal and Doom Metal)
- Mercyful Fate (mostly on Melissa, though their later works still have elements of this; in any case, they have been a major influence on the genre as a whole)
- Meshuggah (a particularly unique case when they started out, although they've since been widely copied)
- Metallica (while, like Megadeth, they are mostly a Thrash Metal or Heavy Metal band, they flirted with this genre on Ride the Lightning and Master of Puppets and dived headfirst into it with ...And Justice for All and arguably also Death Magnetic, to the extent that they are considered a "Prog-Related" band on Prog Archives. As with Maiden, they could also be considered an Ur-Example of the genre)
- Ride the Lightning (1984)
- Master of Puppets (1986)
- ...And Justice for All (1988)
- Mirrorthrone (mixed with Avant-Garde Metal and Black Metal)
- Mnemic
- Moonsorrow (not so much to begin with, but their albums beginning with Kivenkantaja have begun incorporating more prog influence, and Viides Luku - Hävitetty and Tulimyrsky are undeniably prog; also Folk Metal)
- Morbus Chron (as of Sweven, mixed with Death Metal)
- Moron Police, a Norwegian Progressive Metal band with comedy rock lyrics (mixed with Progressive Rock).
- Mudvayne (LD 50 onward. One of the few bands to overlap with this and Nu Metal)
- LD 50 (2000)
- The End Of All Things To Come (2002)
- Lost And Found (2005)
- The New Game (2008)
- Mudvayne (2009)
- Christian Muenzner
- Murmur (self-titled onward; slight Black Metal influence, as well as a lot of Zeuhl influence)
- Mutyumu
- Myrath (mixed with Power Metal and Folk Metal)
- Nagelfar (mixed with Black Metal; not to be confused with Sweden's similarly spelled Naglfar, who are melodic black metal)
- Native Construct
- Ne Obliviscaris (mixed with a bunch of other styles including Progressive Death Metal and Black Metal)
- Nevermore
- Nocte Obducta (mixed with Black Metal and Avant-Garde Metal)
- Noneuclid (mixed with death metal, also some avant-garde touches)
- Northlane (also Metalcore)
- Nothing More (mixed with Alternative Metal)
- Obliveon (along with Thrash Metal)
- Obscura (along with Technical Death Metal)
- The Ocean (with influences drawn from Post-Rock and Sludge Metal)
- Oceans Ate Alaska (mixed with Metalcore)
- Oceans of Slumber (also Gothic Metal, a bit of a Genre-Busting example)
- Ok Goodnight
- Onesidezero (mixed with Alternative Metal and Post-Grunge)
- Opeth (mixed with Death Metal, though Heritage turned them into full-fledged Progressive Rock band for good after experimenting with that approach on Damnation)
- 1999 - Still Life
- 2001 - Blackwater Park
- 2002/03 - Deliverance & Damnation
- Orphaned Land (mixed with Folk Metal, Death Metal, and Doom Metal among other influences)
- Pain of Salvation
- Pelican
- Periphery
- Persefone (Overlaps with Symphonic, Melodic, Technical and Death Metal, their early years also had a good influence of Neoclassical, with their recent entries having some oriental folk flavor)
- Pestilence
- Pharaoh (mixed with Power Metal)
- Porcupine Tree (starting with In Absentia and getting heavier ever since; formerly Progressive Rock / Psychedelic Rock)
- Protest the Hero
- Proyecto Eskhata
- Puya (mixed with jazz and salsa)
- Pyrrhon (mixed with mathcore)
- Queensrÿche (with strong traditional heavy metal influences)
- Operation: Mindcrime (1988)
- Redemption
- Re Vamp
- Riverside
- Rivers of Nihil (earlier material overlaps with Technical Death Metal, which they almost entirely abandoned for prog circa Where Owls Know My Name)
- Rolo Tomassi
- Jordan Rudess
- Savatage
- Streets: A Rock Opera (1991)
- Handful of Rain (1994)
- Dead Winter Dead (1995)
- The Wake of Magellan (1998)
- Poets and Madmen (2001)
- Scar Symmetry
- Serdce (along with Death Metal)
- Seventh Wonder
- Shadow Gallery
- Shining (Norway) (more than a slight case of Genre-Busting, as they also incorporate elements of Industrial Metal, Black Metal, fusion jazz, and numerous other styles. Blackjazz marks the point where their material becomes consistently metal-oriented; before that, most of their material was acoustic jazz or progressive rock, although their live shows had always incorporated quite a lot of metal influence, and scattered songs on In the Kingdom of Kitsch You Will Be a Monster and Grindstone also qualify as metal)
- Shining (Sweden) (started out as Black Metal, but starting around Född förlorare and especially with Everyone, Everything, Everywhere, Ends, they are undeniably a prog metal band now)
- SikTh (also Nu Metal)
- Sigh (also Black Metal, Avant-Garde Metal, and practitioners of extreme Genre Roulette)
- Sleepytime Gorilla Museum
- Brendon Small
- 2012 - Brendon Small's Galaktikon
- Sonata Arctica (started as a Power Metal band with some progressive elements, went pure progressive with Unia and fused power and progressive evenly with The Days of Grays)
- Spiritbox (Spiritual Successor to iwrestledabearonce, also metalcore)
- Starset (along with electronic rock, symphonic elements, and various other styles)
- Stemage (AKA the guy who does the 'Metroid Metal' project)
- Strapping Young Lad (Also Death Metal, Industrial Metal, and Thrash Metal)
- Sylosis
- Symphony X (crosses over with Power Metal and Symphonic Metal)
- Tesseract
- Theocracy (mixed with Power Metal)
- Therion (also Symphonic Metal and Avant-Garde Metal, for both of which they are significant Trope Codifiers, as well as Death Metal on their earliest recordings)
- Thought Industry, also Thrash Metal
- Threshold
- Toehider
- tool (also Alternative Metal, Post-Metal, and a large variety of other genres)
- Tourniquet (also Thrash Metal)
- Devin Townsend (mixed with Death Metal and Industrial Metal on some of his releases, while others are straight-up Progressive Rock)
- 1997 - Ocean Machine: Biomech
- 2007 - Ziltoid the Omniscient
- 2009 - Addicted
- 2014 - Dark Matters
- Tribulation (circa The Formulas of Death)
- Týr (mixed with Folk Metal)
- Nobuo Uematsu with his bands The Black Mages and Earthbound Papas
- UmphreysMcgee (Improg)
- Vektor (along with Thrash Metal)
- Vhol (major case of Genre-Busting, but this is one of the few things that could potentially stick)
- Vision Divine
- Voivod (though their earlier albums were Thrash Metal)
- Watchtower (also Thrash Metal and Power Metal, another possible Ur-Example)
- While Heaven Wept (overlaps with Doom Metal)
- Winger (along with Glam Metal)
- Witherfall (also power metal)
- Wormed (along with Technical Death Metal)
- Wuthering Heights
- X Japan
- Yngwie Malmsteen ( basically The example of Neo Classical Metal)
- YUP
Tropes that apply to progressive metal:
- Epic Rocking: Commonplace to the point where it is very nearly a defining aspect of the genre; no less a source than Prog Archives itself notes that "tracks of longer duration" are ubiquitous. There are a few acts in the genre that don't use it consistently - in fact, Atheist don't even have any songs that scratch the six-minute mark - but they are by far the exception rather than the rule. Most of the most popular acts in the genre have numerous songs that top the ten-minute mark, such as Dream Theaternote , toolnote , Porcupine Treenote , Opethnote ... a complete list of bands and songs would undoubtedly double the length of this article. In fact, there's a contingent of prog metal fans who would argue that if you aren't using this trope, then you aren't really a prog metal band, though it should be emphasised these fans are very much in the minority - most metal fans won't argue much if you cite Atheist as one of the founders of progressive death metal.
- Genre Popularizer: The first major chart success for a prog metal act was either Queensrÿche's "Silent Lucidity" (1990) or Dream Theater's "Pull Me Under" (1991), depending upon your definition. "Silent Lucidity" came earlier, but it isn't a metal song. "Pull Me Under" is.
- Three Chords and the Truth: Subverted, averted and downplayed, all at the same time, given the genre is usually a total inversion to the trope.
- Trope Codifier: Dream Theater, in that nearly every act afterwards has been influenced by them in some fashion (even if that fashion is merely "trying not to imitate Dream Theater").
- Uncommon Time: A staple of the genre; per Wikipedia, the genre is marked by "complex rhythms with frequent meter changes and intense syncopation." Nearly every band in the genre has utilised this frequently, though some are more blatant about it than others (we'll just say there's a reason that Dream Theater provides the image for this trope). There are a reasonable number of listeners who simply won't consider a band to be prog metal if they don't employ this trope.
- Ur-Example: Potential contenders depending upon one's definition of the genre, going in rough chronological order:
- King Crimson: "21st Century Schizoid Man" (1969) is a particularly strong argument, between the Metal Scream Greg Lake employed, the incredibly heavy (for the time) guitars, and the incredibly complex instrumentation. Wikipedia notes in its article on progressive metal that King Crimson "maintained their musical innovation while incorporating a harder approach, using dissonance and experimental tones, yet still maintaining a relationship to the power chords of hard rock."note King Crimson have several other tracks that can qualify as Ur-Examples, but parts one and two of "Larks' Tongues in Aspic" (both 1973) and "Red" (1974) stand out in particular.
- Deep Purple: Straddled the line between conventional hard rock/proto-metal and prog rock. Also known for the sheer virtuosity of it's members, with Richie Blackmore and Jon Lord basically inventing neoclassical metal, and to a lesser extent power metal, with Blackmore in particular being considered by many to be the first "shredder", a style readily adopted by progressive guitarists the world over. Also well-known for their extremely intricate, long composition, the longest of which being over twelve minutes long. Also dabbled in odd time signatures and abrupt tempo shifts, and cited as an influence on many a progressive bands.
- Led Zeppelin: Although not typically considered a prog rock band, they did dabble in the genre occasionally, most famously with their Signature Song "Stairway to Heaven" from their officially untitled fourth album (1971), which even That Other Wiki lists as a progressive rock song. Other songs that could be considered to bolster their prog credentials are "The Rain Song" (1973), "No Quarter" (1973), "Kashmir" (1975), and "Achilles Last Stand" (1977). Not all of these songs could be considered metal, but it's difficult to deny Led Zeppelin's influence on progressive metal.
- Uriah Heep: A co-Trope Maker or Ur-Example for Heavy Metal, they also have fairly high prog cred thanks especially to their sixteen-minute epic "Salisbury" (1971), which features a twenty-four-piece orchestra; no less a source than Allmusic notes the album's "blend of heavy metal power and prog rock complexity." They are one of several cases where a band playing these styles when they had been Unbuilt Tropes makes them a potential Ur-Example for fusions of those styles.
- Van der Graaf Generator are a strange case in that they manage to be as heavy as many progressive metal bands without using electric guitars much. This is accomplished in large part through the central role of brass instruments and organ (which, under the right circumstances, can have a heaviness similar to that of guitars) and Peter Hammill's intense Metal Scream.
- Yes' live material, most notably the live performance of "The Fish (Schindleria praematurus)" on Yessongs (recorded 1972, released 1973), could sometimes have the power and intensity of heavy metal. As for their studio efforts, their otherwise divisive 1980 album Drama features heavier riffing from Steve Howe than had ever before, particularly on the opening track "Machine Messiah", a song which Mike Portnoy cited as an influence. Bassist Chris Squire is also highly revered for his incredibly distinctive, aggressive playing, and his distortive, metallic bass tone, being considered some what of a patron saint among prog bassists.
- Queen's first four albums, particularly Queen II (1974), which features several suites (running about eight to twelve minutes apiece) of interconnected, complex songs that feature numerous overdubs ("The March of the Black Queen" in particular reportedly had so many overdubs that the sixteen-track tape wore thin enough to become transparent) and plenty of segments that are heavy enough to qualify as metal by the standards of the time, though not every song does so (the second half of the album qualifies more so than the first). A Night at the Opera (1975) is a good argument for their inclusion on this list as well, particularly "Death on Two Legs" (with its neoclassical intro segueing into one of the heaviest songs on the album), "The Prophet's Song", and of course "Bohemian Rhapsody".
- Rush: "2112" (1976) is a particularly relevant example here, being a twenty-minute, seven-part epic with several segments that nearly qualify as metal; Wikipedia qualifies it as a progressive metal album. They moved even closer to progressive metal on some of their later material, especially their swan song, Clockwork Angels (2012), a complex concept album rooted in hard rock and metal riffs.
- Diamond Head: A New Wave of British Heavy Metal band who served as a major influence on Thrash Metal bands like Metallica and Megadeth; they also created multi-part epics like "Am I Evil?" (1980) which have pretty high prog cred.
- Angel Witch: Another NWOBHM act who was cited as an influence by many early prog acts, and played significantly more complex and technical material with numerous tempo shifts.
- Mercyful Fate: Danish Heavy Metal band whose sense of theatricality and long compositions were strongly influenced by progressive rock. Their debut, Melissa (1983), has as its centrepiece the 11-minute "Satan's Fall", and that's not all. Although not typically considered a progressive metal band themselves, they are extremely important to the development of the genre. Some of their recordings are more overtly influenced by progressive rock than others are; the title track of Dead Again (1998), another notable case, runs for some 13:40.
- Iron Maiden: Without a doubt the most commercially successful band to emerge from the NWOBHM, they also created multi-part epics such as "The Rime of the Ancient Mariner" and "Powerslave" (both 1984, reaching nearly 14 minutes and 7 minutes respectively) and "Seventh Son of a Seventh Son" (1988, reaching 10 minutes) that qualified as prog. They embraced progressive metal even further when their classic lineup reformed starting in the 2000s, with The Book of Souls (2015) containing the 18-minute "Empire of the Clouds" - and that's not all.
- Metallica: ...And Justice For All (1988), also listed as prog metal on Wikipedia, had several tracks that ran for almost ten minutes, but even before then, Ride the Lightning (1984) and Master of Puppets (1986) had several tracks with multiple segments that ran for seven or eight minutes.
- Recently, Wikipedia also considers Death Magnetic (2008) as prog metal, given its similar-to-AJFA structure combined with Load/Reload's experimentation.
- Megadeth: The Chris Poland/Gar Samuelson lineup was significantly more technical and complex than their peers, featuring numerous non-standard song structures with multiple tempo changes, as well as prominent jazz fusion elements from Poland and Samuelson's shared backgrounds. 1990's Rust in Peace, meanwhile, descended particularly deep into progressive metal territory, especially on tracks like "Holy Wars... The Punishment Due" and "Five Magics".
- Watchtower: Extremely technical Thrash Metal band whose material is often cited as an early example of progressive metal due to its complexity (see their usage of Uncommon Time and Epic Rocking); their work has been cited as a major influence by numerous other prog metal bands, such as Dream Theater, Atheist, Spiral Architect, and Death. The website Allmusic writes that Watchtower's debut, Energetic Disassembly (1985) "is generally considered to be the recording most responsible for the development of the progressive metal genre" and "set the bar for complexity and technique for all who followed."
- Warlord: They had far more elaborate and complex songs than the rest of their Los Angeles peers, with Rainbow and Jethro Tull cited as major influences, while founding drummer Mark Zonder (who would later join Fates Warning) brought a jazz background that lent a further air of sophistication.
- Fates Warning: Early albums such as The Spectre Within (1985) and Awaken the Guardian (1986) show them developing increasing progressive tendencies; No Exit (1988), with the twenty-one-minute "The Ivory Gates of Dreams" taking up the entire second side, is an even more noteworthy argument. They have also been cited as a key influence by later bands, particularly Dream Theater.