UMUR "Shades of Insanity" is a single release by Dutch death/thrash metal act Nocturn. The single was released through Old World Records in 1990. Nocturn formed in 1989 and were a relatively short-lived act releasing this single and their debut full-length studio album "Estranged Dimensions" (May 1991) before disbanding.

The A-side would appear in re-recorded form on "Estranged Dimensions", but the B-side track "Travelling Beyond" is exclusive to this single release (although a re-recorded version of the track was available as a bonus track on the CD version of "Estranged Dimensions" (1991)). Stylistically Nocturn play an aggressive and powerful type of death/thrash metal with a raw snarling vocalist in front. The music is predominantly technically well played and fast-paced thrash metal, but there are occasionally heavier death metal traits to be found. Artists like Invocator, Merciless, and fellow countrymen Dead Head are valid references (there is a Kreator influence here too).

"Shades of Insanity" features a raw, orgaic, and powerful sounding production, which suits the material well. It´s unpolished and perfectly suits the unhinged and ferocious nature of the material. Upon conclusion "Shades of Insanity" is a good quality death/thrash metal release and it´s recommendable to fans of the genre. Nocturn may be one of the more obscure artists on the scene, but their music is well worth investiging further. A 3.5 star (70%) rating is deserved.