Cream were a 1960s British rock supergroup power trio consisting of bassist/singer Jack Bruce, drummer Ginger Baker, and guitarist/singer Eric Clapton. Their unique sound was characterised by a hybrid of blues rock, hard rock and psychedelic rock, combining psychedelia themes, Clapton’s bluesguitar playing, Bruce’s powerful, versatile vocals and prominent bass playing, Baker’s pulsating, jazz-influenced drumming and Pete Brown’s poetry-inspired lyrics. The group’s third album, Wheels of Fire, was the world’s first platinum-selling double album. The band is widely regarded as being the world’s first successful supergroup. In their career, they sold more than 15 million albums worldwide.Their music included songs based on traditional blues such as “Crossroads” and “Spoonful”, and modern blues such as “Born Under a Bad Sign”, as well as more eccentric songs such as “Strange Brew”, “Tales of Brave Ulysses” and “Toad”. (Text and image taken from Wikipedia)
Cirith Ungol has played covers of Cream. Unfortunately I have no info about which, when and where.