Question: Vinland Saga is the second full-length album by a symphonic metal band that has released how many studio albums?
Context: Leaves' Eyes is a German-Norwegian symphonic metal band from Stavanger, Norway and Ludwigsburg, Germany.  They were formed in 2003 by Liv Kristine, the former lead singer of Theatre of Tragedy and the entire line-up of Atrocity.  To date, the band has released six studio albums, a single, six EPs, one live album and a DVD. Elegy is a Maxi single/EP by symphonic metal band Leaves' Eyes, released on 2 May 2005.  Almost all vocals are by the Norwegian singer Liv Kristine, with some backing "growls" by her husband Alexander Krull.  The song "Elegy" is taken from the then upcoming album "Vinland Saga", and a further track from that album, "Solemn Sea" is also included in demo form.  The rest of the tracks are exclusive to this release, but unlike the following EP "Legend Land", they do not share the Vinland theme. April Rain is the second full-length album by the Dutch symphonic metal band, Delain.  It was released in the Benelux on 20 March 2009 and was released internationally on 30 March 2009 by Roadrunner Records.  It was released in Australia on 10 April 2009. Legend Land is an EP by the symphonic metal band Leaves' Eyes, released on June 2, 2006 as a follow-up to the album "Vinland Saga".  Almost all vocals are by Liv Kristine, but there are also some death growls in the tracks "Legend Land", "Viking's Word", and "The Crossing" provided by Alexander Krull. Awaking the Centuries is the second full-length album by German symphonic metal band Haggard.  It was released on February 7, 2000 by Drakkar Entertainment.  The album is based on Michel De Nostredame (Nostradamus) and his experience during The Black Plague in Medieval Europe.  The album features several compositions based on Sergei Rachmaninoff's music. Vinland Saga is the second full-length album by the symphonic metal band Leaves' Eyes, released in 2005.  It is a concept album that tells the story of the voyage of the Norse explorer Leif Erikson and his discovery of Vinland (a.k.a. Newfoundland).  The main vocals are by the Norwegian singer Liv Kristine, but some harsh vocals performed by her husband and producer Alexander Krull can be heard on the songs "Solemn Sea", "The Thorn", and "New Found Land". Agrimonia is a crust punk and sludge metal band from Sweden.  Formed in 2005, the band released its self-titled demo in 2008 before releasing its first full-length, "Host of the Winged", in 2010.  Their second full-length album, "Rites of Separation", was released in 2013.  Major music websites such as Pitchfork have lauded the band's unique style and given it strong reviews, including an 8.0/10 for their second full-length album.  The band is currently signed to Southern Lord Records, an American heavy metal label. David Martijn Westerholt (born 30 March 1979 in Waddinxveen, Netherlands) is the cofounder (along with Charlotte Wessels), keyboardist, and the main songwriter of the Dutch symphonic metal band Delain.  He was previously a member of symphonic metal band Within Temptation, until he was diagnosed with infectious mononucleosis shortly after the release of Within Temptation's second full-length studio album, "Mother Earth".  His brother Robert Westerholt is the guitarist and founder of Within Temptation.  He currently lives in Zwolle, where he resides since his study in Communication at Windesheim College in 1998. Storm of the Light's Bane is the second full-length album by the Swedish black metal band Dissection.  The album was released on November 17, 1995 by Nuclear Blast Records.  This would be the band's last full-length album before Nödtveidt's 1997 incarceration for the felony murder of Josef ben Meddour.  It would not be until 2006 that they would release their third and final album "Reinkaos", which was followed by Jon Nödtveidt's suicide and the breakup of the band.  As with the band's debut album, Kristian 'Necrolord' Wåhlin created the artwork.  The album is widely considered a masterpiece and one of the best black metal albums ever written.  It has had significant influence on the development of extreme metal, inspiring many bands such as Watain, whose frontman played bass live with the band during their final shows. Invisible Circles is the third studio album by Dutch symphonic metal band After Forever.  It was released on 25 March 2004, by the small Dutch label Transmission Records.  It is After Forever's first full-length album since the dismissal of guitarist and composer Mark Jansen, whose musical tastes had strongly influenced the sound of their first work "Prison of Desire" (2000) and their successful second offering "Decipher" (2001).  In this work After Forever choose a new musical direction, mostly revolving around elements of progressive metal instead of the gothic and symphonic metal of previous albums.  The creative process for "Invisible Circles" took more than a year and required the use of three recording studios in the Netherlands and Germany.  A long tour to support the album brought the band to some of the most important European rock festivals and to Central and South America.
Answer: six