Yeah no skillbook for Dust Devil and only one for whirlwind, these are the 2 special skills Man-at-Arms have. Also get Flurry, Rage, Melee Power Stance, these are the best attack skills for Man-At-Arms. Crippling blow, eroding strike and draw blood are not nearly as useful, I think.

You will want both if you play a melee fighter. They do the same thing but WHirlwind causes more damage, use one then the other if anyone is still standing.

Did you find Whirlwind?