Rivera started his career at age 13 as a DJ in his native Spanish Harlem. He began producing house music in 1992, specializing in a more soulful sound. He has worked under a variety of pseudonyms, including Kings of Tomorrow, Soul Vision and Mysterious People, either alone or with partners Jose Burgos, HAZE and Jay 'Sinister' Sealee (Rivera has parted ways with Sealee in 2002). He is the owner of labels BlackWiz (founded 1993) and Deep Vision Records (founded 1995).
Rivera's best known track is "Finally", released in 2000 as Kings of Tomorrow on Defected Records, with vocals by Julie McKnight, which peaked at number 24 in the UK Singles Chart and at number 17 on the Billboard dance chart, and appeared in a large number of compilations from labels such as Ministry Of Sound, Hed Kandi and Warner Music. The track is included in K.O.T.'s first album It's in the Lifestyle. The same album also yielded the track "Young Hearts". The vocal version of "Finally" was also used as a part.