What Chicago collective had a member release a free mixtape?
Save Money
Title: Chance the Rapper
Passage: Chancellor Johnathan Bennett (born April 16, 1993), known professionally as Chance the Rapper, is an American rapper, singer, songwriter, record producer, and actor from the West Chatham neighborhood of Chicago, Illinois.  In 2013, he began to gain recognition following the release of his second mixtape, "Acid Rap".  Apart from his solo career, he is a member of the Chicago collective Save Money (along with frequent collaborator Vic Mensa).  He has worked as the lead vocalist for the band The Social Experiment; they released the album "Surf" in May 2015.
Title: Illmind
Passage: Ramon Ibanga, Jr., professionally known as Illmind (often stylized as ! llmind) is a Filipino American hip hop producer and educator from Bloomfield, New Jersey.  He has co-written and produced hip-hop, pop, soul, and electronic music for labels such as Cash Money, Def Jam, and Aftermath, and has worked with artists such as Andy Mineo, Kanye West, Drake, J. Cole, Dr. Dre, Ludacris, 50 Cent, Ariana Grande, and others.  His accomplishments in 2016 include production on the new Hamilton Mixtape and Disney's Moana (2016 film), both created by Lin-Manuel Miranda.  ! llmind has released several studio albums and had a number of songs and albums reach the music charts.  His most recent album, "Human", is a collaboration with Joell Ortiz, and was released on July 17, 2015.  Starting in 2008 ! llmind has released the free mixtape series "Blaps, Rhymes & Life," and he operates a producer showcase in New York city called Beats, Love, Alcohol & Party (B.L.A.P.).  Since 2011 he has released instrumental albums and "producer drum kit" albums for music producers dubbed his "Blap-Kit" sound packs.  He established his own multi-genre music company Roseville Music Group in 2014.
Title: Free (Based Freestyles Mixtape)
Passage: Free (Based Freestyles Mixtape) is a collaborative mixtape by American rappers Lil B and Chance the Rapper.  It was released for free on August 5, 2015.
Free (Based Freestyles Mixtape) Chance the Rapper