Heavy metal music
Critics disagree over who can be thought of as the first heavy metal band. Most credit either Led Zeppelin or Black Sabbath, with American commentators tending to favour Led Zeppelin and British commentators tending to favour Black Sabbath, though many give equal credit to both. A few commentators—mainly American—argue for other groups including Iron Butterfly, Steppenwolf or Blue Cheer. Deep Purple, the third band in what is sometimes considered the "unholy trinity" of heavy metal (Black Sabbath, Led Zeppelin, and Deep Purple), despite being slightly older than Black Sabbath and Led Zeppelin, fluctuated between many rock styles until late 1969 when they took a heavy metal direction.
Dragonslayer (band)
Dragonslayer were an English heavy metal band from Lancashire, formed in 1978 as Heavy Thunder. They are a respected band from the new wave of British heavy metal period who settled on the name Slayer in 1980, meaning (as with S.A Slayer) they had to change their title to Dragonslayer to avoid confusion with the thrash band Slayer from Los Angeles, who released their debut album "Show No Mercy" worldwide on 3 December 1983. They can be described as early Power Metal, sharing classic rock influences with and fantasy themed lyrics with other N.W.O.B.H.M. bands from the West Midlands such as Tyrant, Cynic, Grim Reaper and Arc.