The Columbine High School massacre was an attack by Eric Harris and Dylan Klebold on their high school on April 20th, 1999 which killed 13 students and one teacher. Most YTPMVs/音MAD's source home videos of theirs or school projects. These include:

• Hitmen For Hire: Eric and Dylan play hitmen-for-hire who bullying victims could turn to when they needed help getting revenge on their bully.
• Rampart Range: Eric and Dylan shooting at a firing range along with friends.
• Radioactive Clothing: A school project created by Eric and Dylan where them and their friends fight against clothes who come to life and attack citizens after an atomic bomb hits their town.

These are usually used for shock value or to make fun of the perpetrators.