"I want to roll dung!! I don't even care what kind it is!!! ...*sigh* Now I'm all upset and confused! Wait, you brought me some dung?! And you're giving it to me? For free? Oh, thank you, thank you, thank you! Yeaaaaaaaah! Let's roll!!! Let's roll to the ends of the desert! Yeah!"
— Wan Sum Dung, upon being given regular Dung

Wan Sum Dung is a character in Mother 3, found only in the Death Desert in Chapter 3. It is a Dung Beetle, but does not consider itself to be one without any Dung to roll around and feels sad. Its name is a pun on 'Want Some Dung', which references this. If Salsa gives Wan Sum Dung the Dung that it desires, it will give Salsa either 5, 10, or 50 experience points depending on its judgement on the Dung's quality.

There is no limit on the amount of Dung that Salsa can give Wan Sum Dung: each time, it accidentally rolls the Dung into the oasis on its east. Before Salsa gives it any Dung, Salsa can be healed by drinking from the oasis with the text "There is cold, clean water here." After the first Dung is accidentally rolled into the water, the text permanently changes to "There is cold, clean water here. ...But it smells kind of dung-like." The healing properties of the water do not change, however.