The legs are like the donkey's, with small, straight-sided hooves. The head is a little narrower than the donkey's, but otherwise very similar. Mules are stronger than horses, with much longer working lives. They rarely become ill or lame or suffer wounds. They are able to withstand extremes of temperature, can live on frugal rations, have tremendous stamina and resilience, and are exceptionally sure-footed.
Mules are highly intelligent and are very quick to learn.
Being so intelligent, a badly handled mule can be a problem. You cannot force him to do anything. You must persuade him, or give him only work that he wants to do. Both the mule and the handler are a lot happier when this approach is followed.