Chigaco-based rapper Vic Mensa did an insanely awesome freestyle over Twenty One Pilots‘ Grammy-nominated song “Heathens”—and even did a Joker-inspired cover art for it.

Read more: Here’s how some of your favorite artists got nominated for a Grammy

His haunting raps give insight to the first-hand violence he experienced while living in Chigaco and a few choice words for police. His freestyle comes after the rapper’s own activism protesting the Dakota Access Pipeline.

Listen to the freestyle below and tell us what you think in the comments.

Twenty One Pilots are nominated in five Grammy categories: Record of the Year, Best Pop Duo/Group Performance, Best Rock Song, Best Song Written for Visual Media and Best Rock Performance.

Watch more: APMAs 2016: TWENTY ONE PILOTS win Artist Of The Year