Illustrations of history

The good thing about a flail is that, while kind of miserable as a weapon in a proper battle with mass formations and such, against a handful of professional opponents it's actually not bad. Very much the weapon of choice of peasant militias. Mail can block an edge or point, like a scythe or a pitchfork, but getting slammed with a big rotating weight will just about always bruise or break bones beneath an enemy's armor. You'd need a lot of padding to prevent that!