premise: Hans Jürgen Kürsch, better known as Hansi Kürsch (born 10 August 1966 in Lank-Latum/Meerbusch, Germany), is a German musician best known for being the co-founder, lead vocalist, co-composer, and lyricist of power metal band Blind Guardian. He was also the bassist in Blind Guardian until the 1998 album "Nightfall in Middle-Earth". He also provides lead vocals for the band Demons and Wizards.
hypothesis: The lead vocalist and former bass player of Blind Guardian is a founding member or a band that has uses the word wizards in it's name. 
reason: Hansi Kursch is the co founder of Blind Guardian and the lead vocalist of Demons and Wizards. There's no mention of who started Demons and Wizards in the snippet I read so he may or may not have been a founding member of both bands. 