J. Cole brought out special guest Chance The Rapper during his concert at University of Illinois at Chicago’s Spark in the Park show last week. The hometown star performed his unreleased song "Thotty," with some help from Cole, who took the second verse.

The song includes a couple quick references to Outkast's "Prototype" and "Ms. Jackson," and with its trap-funk beat and the two MCs spitting, the ATLien vibes were strong in Chi-Town.

Check it out up top.

[via Hip Hop N More]