The 120 stars reward in SM64 which unlocks the canon the the castle courtyard, which allows Mario to reach the top of the castle & speak to Yoshi. Yoshi gives you up to 100 lives, which in turn gives you a shiny triple jump. Yay..?

Below is a link to my SM64 playlist, which contains all of my Mario 64 gameplay videos:    • Super Mario 64 100% Walkthrough  

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