My favorite Butkus story was he was coming off the field after stopping the opposing team. As he passed his own QB, he grabbed his face mask and snarled in his face, "Hold 'em." The Bears have always been about defense.
A legend among legends in the NFL. Toughest NFLer ever? Hardest hitting? Could very well be. His name is synonymous with hard hitting, tough playing. You just have to say Butkus and everyone knows what you mean. Very very few instances of that.
Having been raised in Chicago and seen him play and seeing him on TV a lot after he retired, he was quite the character. On the field, he'd make the hardest tackles you'll ever see. Then he'd step on the guy's throat as he got up. Mean SOB. Off the field, he was a sweetheart, and very funny. Making it to 80 is remarkable for an ex football player. Many live only into their 50s. One of the toughest things about getting older is seeing famous people you grew up with pass away. RIP Butkis!