pound for pound a tibetan mastiff is it.... they are bred to be chained during day and roam at night.(name in tibet is (Do-khyi) they fight off snow leopards and have the thickest bone density for their size and have been around since the bronze age(one of oldest dogs).. pit bulls are decendants of tibetan mastiff's just as well as english mastiff's etc..... i aint talking about some 100lb akc one that comes from the englishman's breed... get one from tibet where females are 160lbs all day and males much larger... since the bronze age they have put these dogs in pits as puppies to let them get mean feeding them scraps of wolf's etc...
dog's bites vary not by too much, but a pit bull isn't even close to strongest... another urban legand about the dog... it's just when they grab something their mentality is not to let go... hence the "lock jaw" also they say it is hard to measure the true bite power of a dog because of their nature... but from the results they do have it's not a pitbull...
the pound for pound was out of dogs... lol tosa inu is a beast too... but they are just for fighting.... tibetan mastiff's actually have use to them and are bred as guardian warriors... not "fighting dogs"
the creature quote.. well pound for pound the list would be huge.... lol and a wolverine/badger is the just retarded pound for pound... a bear or even a pack of wolves won't even think about taking a meal from one of those guys...