Background: Kevin Patrick Shields was born on 21 May 1963 in Jamaica Hospital in Queens, New York City, United States. He is the eldest of five siblings born to Irish parents; his mother was a nurse and his father was an executive in the food industry. Shields' parents had emigrated to the United States from Ireland in the 1950s, when the couple were teenagers. Shields attended Christ the King, a Roman Catholic primary school which he described as "a really horrible school run by psychopathic nuns".
Context: Shields' guitar sound has been cited as one of the most recognisable aspects of My Bloody Valentine's music. His sound uses "texture more than technique to create vivid soundscapes". He has been listed at number 95 and 2  on Rolling Stone's and Spin's 100 Greatest Guitarists of All Time list. During the late 1980s, Shields began customising the tremolo systems for his Fender Jaguars and Jazzmaster guitars; he extended the tremolo arm and loosened it considerably, to allow him to manipulate the arm while strumming chords, which resulted in significant pitch bending. Shields used a number of alternate and open tunings that together with his tremolo manipulation, according to Rolling Stone's Michael Azerrad, achieved "a strange warping effect that makes the music wander in and out of focus".  Among Shields' notable effects is digital reverse reverb, sourced from a Yamaha SPX90 effects unit. Together with the tremolo manipulation and distortion, he created a technique known as "glide guitar". Shields effects rig, which is composed largely of distortion, graphic equalisers and tone controls, consists of at least 30 effects pedals. His rig is connected to a large number of amplifiers which are often set to maximum volume to increase sustain. During live performances with My Bloody Valentine - particularly during the closing "You Made Me Realise" - Shields creates a blend of noise and excessive feedback, known as "the holocaust", which has often lasted for half an hour and often reached 130db. "It was so loud it was like sensory deprivation," he remarked. "We just liked the fact that we could see a change in the audience at a certain point."  Shields' sound and performance have been regarded as influential, with musicians including Billy Corgan and J Mascis citing him as an influence.  "Kevin Shields achieved something on Loveless that only the great guitarists achieve: he achieved a wholeness and a unity," observed Living Colour's Vernon Reid. "He created his own sound."
Question: where did he learn these techniques?
Answer: with musicians including Billy Corgan and J Mascis

Background: Mayhem is a Norwegian black metal band formed in 1984 in Oslo. They were one of the founders of the Norwegian black metal scene and their music has strongly influenced the black metal genre. Mayhem's early career was highly controversial, primarily due to their notorious live performances, the 1991 suicide of vocalist Per Yngve Ohlin ("Dead") and the 1993 murder of guitarist Oystein Aarseth ("Euronymous") by former member Varg Vikernes ("Count Grishnackh"), of Burzum. The group released a demo and an EP that were highly influential, and amassed a loyal following through sporadic and notorious live performances, attracting further attention through their ties to the string of Norwegian church burnings and the incidents of violence surrounding them.
Context: Statements of imminent touring plans were announced on the band's web page a few weeks after their final dates with Blasphemer. In October 2008, Krister Dreyer ("Morfeus") of Dimension F3H and Limbonic Art joined the group as touring guitarist for their upcoming South America Fucking Armageddon tour.  The band toured through late 2008 and 2009 with this lineup, prior to announcing Summer 2009 dates with Silmaeth, a French musician, as a second touring guitar. In November 2009, the band was arrested in Tilburg, Netherlands, after destroying a hotel room while on tour. Norwegian guitarist Teloch of Nidingr replaced Silmaeth in February 2011, and performed with the group before departing the following year.  In an interview in 2012, Necrobutcher revealed that Mayhem had begun work on their fifth studio album. As of November 2013, the new album was being mixed, with an early 2014 release date expected. Several months later, on February 18, 2014, it was announced that Mayhem would release a new album in May 2014, with a new song "Psywar" made available for streaming.  On February 20, 2014, the band's record label, Season of Mist, announced that the new album Esoteric Warfare would be released worldwide on May 27, 2014. This marked the first Mayhem studio effort since Blasphemer's departure and Teloch's permanent status in the band.  In January 2015, Mayhem, Watain, and Revenge played together as part of the "Black Metal Warfare" tour in the United States. Mayhem and Watain toured again in the United States in November 2015 with Rotting Christ as "Part II" of the previous tour.
Question: What happened in 2008?
Answer:
In October 2008, Krister Dreyer ("Morfeus") of Dimension F3H and Limbonic Art joined the group as touring guitarist for their upcoming South America Fucking Armageddon tour.