After single-handedly redefining "warped" as the mind and mouth behind the Bronx-based Ultramagnetic MCs, "Kool" Keith Thornton -- aka Rhythm X, aka Dr. Octagon, aka Dr. Dooom, aka Mr. Gerbik -- headed for the outer reaches of the stratosphere with a variety of solo projects. A one-time psychiatric patient at Bellevue, Keith's lyrical thematics remained as free-flowing here as they ever were with the NY trio, connecting up complex meters with fierce, layers-deep metaphors and veiled criticisms of those who "water down the sound that comes from the ghetto." His own debut single, "Earth People" by Dr. Octagon, was quietly released in late 1995 on the San Francisco-based Bulk Recordings, and the track spread like wildfire through the hip-hop underground, as did the subsequent self-titled full-length released the following year. Featuring internationally renowned DJ Q-Bert (also of the Invisible Skratch Picklz) on turntables, as well as the Automator and DJ Shadow behind the boards, Dr. Octagon's left-field fusion of sound collage, fierce turntable work, and bizarre, impressionistic rapping found audiences in the most unlikely of places, from hardcore hip-hop heads to jaded rock critics. Although a somewhat sophomoric preoccupation with body parts and scatology tended to dominate the album, Keith's complex weave of associations and shifting references is quite often amazing in its intricacy. The record found its way to the UK-based abstract hip-hop imprint Mo'Wax (for whom Shadow also records) in mid-1996, and was licensed by the label for European release (Mo'Wax also released a DJ-friendly instrumental version of the album titled, appropriately, The Instrumentalyst [Octagon Beats]).

The widespread popularity of the album eventually landed Keith at Geffen splinter DreamWorks in 1997; the label gave Dr. Octagon (retitled Dr. Octagonecolygist) its third release mid-year, adding a number of bonus cuts. In early 1999, however, Keith's alter-ego Dr. Dooom unfortunately "killed off" Dr. Octagon on the opening track of First Come, First Served (released on Thornton's own Funky Ass label). Kool Keith signed to Ruffhouse/MCA for his second album under that alias, 1999's Black Elvis/Lost in Space. Records released as Kool Keith followed in 2000 (Matthew) and 2001 (Spankmaster), while the 2002 collaboration Gene appeared as KHM (Kool Keith plus H-Bomb and Marc Live). His next project was a four-rapper group named Thee Undatakerz with Keith taking on a new persona, Reverand Tom. Kool Keith Presents Thee Undatakerz hit the streets in May of 2004. Keeping busy, Keith released Diesel Truckers in August of the same year with old friend/producer Kutmasta Kurt. ~ Sean Cooper, All Music Guide