Question: In which year was this Swedish avant-garde metal band formed, whose founding members include Johannes Bergion?

Context articles: Marcin Rygiel
Cleric (band)
Pandora's Piñata
Diablo Swing Orchestra
Pan.Thy.Monium
Within Reason
Pacifisticuffs
Johannes Bergion
The Butcher's Ballroom
What's He Building in There?

Marcin "Martin" Rygiel, (born 30 April 1983 in Krosno, Poland), is a Polish musician, best known as the former bass guitarist of the technical death metal band Decapitated from 1997 to 2007, leaving several months before their hiatus.
 He was also a member of the avant-garde metal/black metal band Lux Occulta from 1998 until their hiatus in 2002.
 In June 2008, Rygiel toured with the death metal band Vader as a session musician.
 In 2010, Rygiel joined California-based death metal band Annihilated as their bassist until 2013.
 He was the bassist for the Egyptian-American death metal band Nader Sadek from 2014 to 2015.
Cleric is an American avant-garde metal band based out of Philadelphia, Pennsylvania, United States.
 Formed in 2003, their initial lineup consisted of guitarist Matt Hollenberg, drummer Larry Kwartowitz, vocalist Nick Shellenberger and bassist Chris Weindel.
 After their first EP Chris Weindel was replaced by James Lynch, who was succeeded by bassist Daniel Ephraim Kennedy in 2012.
 Informed by metal pioneers such as Meshuggah, Converge, Fantômas, and Neurosis, the band is known for their experimental approach to grindcore, doom and avant-garde metal.
Pandora's Piñata is the third studio album by Swedish avant-garde metal band Diablo Swing Orchestra.
 It was released on May 14, 2012 in Europe through Candlelight Records and on May 22, 2012 in North America through Sensory Records.
Diablo Swing Orchestra is a Swedish avant-garde metal band formed in 2003.
 They have released three albums: "The Butcher's Ballroom" (2006), "Sing Along Songs for the Damned & Delirious" (2009), and "Pandora's Piñata" (2012).
Pan.Thy.Monium was a Swedish avant-garde metal band formed and led by Dan Swanö with several members from another project of his, Edge of Sanity.
 The group disbanded in 1996, after recording "Khaooohs and Kon-Fus-Ion".
Within Reason is an American rock band from Birmingham, Alabama, whose founding members include Chris Dow and David Koonce.
 The band was formed in 2005.
Pacifisticuffs is the upcoming fourth studio album by Swedish avant-garde metal band Diablo Swing Orchestra.
 It is currently planned for an October 2017 release.
Johannes Bergion is a Swedish cellist, songwriter and backing vocalist, most known for being one of the founding members of avant-garde metal band Diablo Swing Orchestra.
 He also played cello in various Hellsongs albums, and in the In Flames album "Sounds of a Playground Fading".
The Butcher's Ballroom is the debut studio album by Swedish avant-garde metal band Diablo Swing Orchestra, released in 2006.
 It features all four songs from their EP and disc debut "Borderline Hymns", along with 9 new songs, for a total of 13 tracks divided into two acts.
 It is the band's first release with singer AnnLouice Lögdlund.
What's He Building in There?
 was a Canadian avant-garde metal band, formed in 2006 in Waterloo.
 The band's music combined elements of funk, avant-garde metal and progressive rock.
 The band, named after a Tom Waits song from "Mule Variations", were known for their live show in which they usually wear outrageous costumes.
 They have been said to "create a sort of audio psychosis that totally envelopes and surrounds the listener like a straight jacket," and their debut album has been described as "an unlikable masterpiece."