Which artist was featured on The Dream Merchant Vol. 2 and was also a part of the duo Black Star.
Mos Def
Title: Mos Def
Passage: Yasiin Bey ( ) (born Dante Terrell Smith; December 11, 1973), best known by his stage name Mos Def ( ), is an American hip hop recording artist, actor and activist from Brooklyn, New York City, New York.  Best known for his music, Mos Def embarked on his hip hop career in 1994, alongside his siblings in the short-lived rap group Urban Thermo Dynamics (UTD), after which he appeared on albums by Da Bush Babees and De La Soul.  He subsequently formed the duo Black Star, alongside fellow Brooklyn-based rapper Talib Kweli, and they released their eponymous debut album in 1998.  He was featured on the roster of Rawkus Records and in 1999 released his solo debut, "Black on Both Sides".  His debut was followed by "The New Danger" (2004), "True Magic" (2006) and "The Ecstatic" (2009).  The editors at About.com listed him as the 14th greatest emcee of all time on their "50 greatest MC's of our time" list.
Title: Black Star (rap duo)
Passage: Black Star is an American hip hop duo formed in 1997, from Brooklyn, New York City, New York.  The duo is composed of rappers Yasiin Bey (Mos Def) and Talib Kweli.  They released a number of singles and one album, "Mos Def & Talib Kweli Are Black Star" on August 26, 1998.  The record received critical acclaim, but only moderate commercial success.  Since then the duo has worked together intermittently on soundtracks and other projects.
Title: The Dream Merchant Vol. 2
Passage: The Dream Merchant Vol.  2 is the second compilation album from producer 9th Wonder, formerly of Little Brother.  It was released on October 9, 2007 through Sixhole Records.  The album has guest appearances by his former group, Little Brother, his fellow Justus League members, Sean Price, Big Dho, L.E.G.A.C.Y., Chaundon, Skyzoo, Keisha Shontelle, Big Treal, The A.L.L.I.E.S., Jozeemo, Tyler Woods, Joe Scudda, Buckshot, Sean Boog, D.O.X., O-Dash, Buddy Klein & Median, also outside performers (including some who 9th worked with) including Torae, Mos Def, Memphis Bleek, Jean Grae, Royce Da 5'9, Vandalyzm, Naledge (½ of Kidz In The Hall), Saigon, Camp Lo, Ness (of Da Band), Strange Fruit Project & Natural Born Spittas.  The album is also marks the debut of then-unknown MC, Rapsody.
Mos Def The Dream Merchant Vol. 2