Perhaps the first example of "dragon rock" -- a style perfected by bands like Iron Maiden and Dio in the early to mid-'80s -- was Ritchie Blackmore's Rainbow, a rather pretentious 1975 collection from the guitarist's first post-Deep Purple project.
Fittingly enough, a young Ronnie James Dio provides the goblin-like frontman presence required by the increasingly Baroque Blackmore.
The young Dio is at his best when he fully gives in to his own and Blackmore's medieval fantasy leanings, in hard-rocking tracks like "Sixteenth Century Greensleeves" and "Man on the Silver Mountain." The dark, trudging doom rock of "Self Portrait" most clearly showcases what they were capable of.
The album's ponderous lyrics are occasionally punctuated by poetic phrases such as "crossbows in the firelight." Rainbow become a true embarrassment when they try to lighten up and boogie down.
"If You Don't Like Rock ]n' Roll" is really an abomination, a pale imitation of second-rate radio-rockers like BTO.
Although Ritchie Blackmore's Rainbow provides a few listenable tracks, its primary value is historical.
Look to Rainbow's next album, Rainbow Rising (1976), to grasp the heavy metal potential that is only hinted at here.