Battle rap

Battle rap (or rap battling) is a type of rapping that includes boasting and bragging. Rap battles are often performed as live contests in front of an audience. Two or more rappers compete to see who has the better verses. The raps can be rehearsed or freestyled. A freestyle battle is where the rappers use improvised lyrics. Battling can also occur on recorded songs.
Each competitor's goal is to insult their opponent through clever lyrics. They must also convince the audience that they are the better rapper. Judges have been used in formal contests. Without judges, the rapper who receives the best response from the audience is viewed as the winner.
ERB.
The YouTube channel Epic Rap Battles of History is based on the idea of famous people from history and well-known fictional characters battle rapping