I remember reading an interview with him: Interviewer: What is your goal every game? Butkus: For the quarterback to wake up, and ask, " Who hit me?" RIP
Watching his highlights it seems like they rewrote the rule book because of him. The way he would headhunt, spin QBs around and throw them to the ground like a rag doll. He would twist players heads around when he grabbed them. He really did play like he was trying to hurt people. Definitely one of the greatest defensive players ever.