Ghost's Name
In Chapter 4, the ghost that you fought and that takes over Mario asks you to guess his name. His name is Doopliss.
Submitted by Hovey. 50% success rate. 

Get Luigi's Clothes
To acquire Luigi's clothes, go to where you get the sixth crystal star. From here, do a spring jump up to a pole on the left side. Do another spring jump to get to a ledge with the Luigi Emblem.
Submitted by Hovey. 

Get Wario's Clothes
To get Wario's clothes, go to the central area of Rougeport with 360 Coins. There should be a merchant with a large moustache. He occasionally sells and item called a Wario Emble.
Submitted by Hovey. 0% success rate. 

Waluigi's Clothes
Equip both the Wario Emblem and the Luigi Emblem at the same time.
Submitted by Hovey. 

Choose Colour of Yoshi
Begin a new game and input a colour as a name. When Yoshi joins your party, he will be the colour you entered.
Submitted by Hovey. 

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