Question: Who played in a death metal band George Thorogood or Mikael Åkerfeldt.?
Context: George Thorogood and the Destroyers is the self-titled debut album by American blues rock band George Thorogood and the Destroyers, released in 1977.  Consisting mostly of covers of blues hits, it included a medley of John Lee Hooker's "House Rent Boogie" and "One Bourbon, One Scotch, One Beer", the latter a song written by Rudy Toombs for Amos Milburn, and later covered by Hooker. Unblessing the Purity is the second EP by Swedish death metal band Bloodbath.  It was released on March 10, 2008, on Peaceville Records.  It is their first release since "Resurrection Through Carnage" to include Mikael Åkerfeldt on vocals.  Per "Sodomizer" Eriksson replaced Dan Swanö on guitar beginning with this EP.  The cover art is by Dusty Peterson, who won the band's contest for fan-made cover art.  The album is packaged in a super-jewel case with a slipcase cut to fit.  "Unblessing the Purity" is only available directly through mail-order via Peaceville Records or Snapper Music, and digitally. Lars Mikael Åkerfeldt (born 17 April 1974) is a Swedish musician, prominently known as the lead vocalist, guitarist, and primary songwriter of progressive death metal band Opeth, as well as being the former vocalist of death metal supergroup Bloodbath.  He was also guitarist for the "one-off" band Steel, and is part of the collaboration Storm Corrosion with Steven Wilson. Sörskogen was a Swedish progressive rock project Mikael Åkerfeldt of Opeth and Dan Swanö started for fun.  Both musicians are known for their wide musical interests.  The project was supposedly named after a small community near the Stockholm suburb Huddinge where Mikael practiced with his first band Eruption in the late 1980s.  At the Opeth concert on December 18, 2008, Mikael Åkerfeldt claimed to have played soccer for the Sörskogen IF soccer club.  Sörskogen is heavily influenced by 1970s prog rock bands, Camel to name but one.  Not much is known about the project, except a few references made by Mikael in interviews. Bloodbath over Bloodstock is a live DVD by Swedish death metal band Bloodbath.  It features the entire live set the band played at Bloodstock Open Air in August 2010.  It was filmed by the production company The Dark Box.  It was released on April 25, 2011, by Peaceville Records.  This is the final release with Mikael Åkerfeldt in the band as he quit in 2012. Heritage is the tenth studio album by Swedish Progressive metal band Opeth.  It was released on 14 September 2011 through Roadrunner Records.  The album was recorded in early 2011 at Atlantis/Metronome Studios in Stockholm and produced by Mikael Åkerfeldt, engineered by Janne Hansson, and mixed by Steven Wilson.  It takes on a full-fledged progressive rock sound, something the band had always wanted to do for some time.  It is a stark contrast to the progressive metal and death metal sounds of their past albums. Watershed is the ninth full-length studio album by the Swedish heavy metal band Opeth.  Released by Roadrunner Records, "Watershed" is the first studio album by Opeth to feature guitarist Fredrik Åkesson and drummer Martin Axenrot, who replaced longtime guitarist Peter Lindgren and drummer Martin Lopez.  The artwork for the album was made by Travis Smith (who has created the artwork for eight previous Opeth releases) in collaboration with Mikael Åkerfeldt.  The album is, as of 2017, the band's last studio album to contain death growls or any death metal elements.  The song "The Lotus Eater" was featured in the video game "".  As of December 8th, 2015, the song "Heir Apparent" is available for download in the video game "Rock Band 4". George Thorogood (born February 24, 1950) is an American musician, singer and songwriter from Wilmington, Delaware.  His "high-energy boogie-blues" sound became a staple of 1980s rock radio, with hits like his original songs "Bad to the Bone" and "I Drink Alone".  He has also helped popularize older songs by American icons, such as "Move It on Over", "Who Do You Love? ", and "House Rent Boogie/One Bourbon, One Scotch, One Beer", which became staples of classic rock radio. Opeth is a Swedish heavy metal band from Stockholm, formed in 1989.  The group has been through several personnel changes, but lead vocalist, guitarist and songwriter Mikael Åkerfeldt has remained Opeth's primary driving force throughout the years.  Opeth has consistently incorporated progressive, folk, blues, classical and jazz influences into its usually lengthy compositions, as well as strong influences from death metal, especially in their early works.  Many songs include acoustic guitar passages and strong dynamic shifts, as well as both death growls and clean vocals.  Opeth is also well known for their incorporation of Mellotrons in their work.  Opeth rarely made live appearances supporting their first four albums; but since conducting their first world tour after the 2001 release of "Blackwater Park", they have led several major world tours. Katatonia is a Swedish metal band formed in Stockholm in 1991 by Jonas Renkse and Anders Nyström.  The band started as a studio-only project for the duo, as an outlet for the band's love of death metal.  Increasing popularity lead them to add more band members for live performances, though outside of the band's founders, the lineup was constantly changing, revolving door of musicians throughout the 1990s, notably including Mikael Åkerfeldt of the band Opeth for a period.  After two death/doom albums, "Dance of December Souls" (1993) and "Brave Murder Day" (1996), problems with Renkse's vocal cords coupled with new musical influences lead the band away from the screamed vocals of death metal to a more traditional, melodic form of heavy metal music.  The band released two more albums, "Discouraged Ones" (1998) and "Tonight's Decision" (1999), before settling into a stable quintet lineup for all of 2000's.  The band released four more albums with said lineup - "Last Fair Deal Gone Down" (2001), "Viva Emptiness" (2003), "The Great Cold Distance" (2006), and "Night Is the New Day" (2009), with the band slowly moving away from their metal sound while adding more progressive rock sounds to their work over time.  While lineup changes started up again into the 2010s, Renkse and Nyström persisted, and the band continued to release music, including "Dead End Kings" (2012) and their most recent, their tenth studio album, "The Fall of Hearts", released on May 20, 2016.
Answer: Mikael Åkerfeldt