I don't mean like single wins but things like Armstrong holding belts from 3 different weight divisions at the same time, Hearns winning belts in 5 divisions, Foreman having a 10 year break then making a comeback and becomming the oldest man to win the title 20 years after he lost it.. What would you add?
Becoming a hw champion in the early 20th cenury while beeing black is an accomplishmen in itself ... and never repeated. Becoming a world champ at age 17. Becoming the hw champ of he world with age 21.
First things that came to mind 12 year reign of Joe Louis + retiring as champion. Duran winning the Middleweight title 17 years after the Lightweight title. Pac winning titles in 7 divisions, 4 of them linear.
patterson first man to become hw champ twice, ali first man to become hw champ 3 times. archie moore holding the most ko's (i believe 138 or something like that). Pep winning a round without even throwing one punch. and so on and so on man there are so manny things that can be marked as a great achievement. i think it's impossible to write them all down.
It's a myth, nothing more. Anyways, at the moment I'm infatuated with "Terrible" Terry McGovern's feat at the turn of the century, probably because I've been discussing it so much lately. The miniature Mike Tyson of the day KO'd all 3 world champions from Bantamweight to Lightweight within a span of 10 months. During that time span he went 5-0 in title bouts at Bantam and Feather (all wins coming by way of KO) and 20-0-1 altogether, winning 18 of those bouts by KO with 16 of them coming within the first 3 rounds. Amazing.
Being champion at one weight for a long time Joe Louis, Benny Leonard and Carlos Monzoon as well as Bernard Hopkins comes to mind. Not that I don't think winning championships in more than one weight class isn't impresive. however as the body grows and gets older it tends to gain weight there fore it is only natrual to move up in weight. Staying at one weight for a long time becomes more diffcult as their career goes on.
Michael Spinks moving up to Heavyweight to beat an undefeated Larry Holmes. Holmes wasn't prime, but neither was Spinks - operating way above his best weight.