suppermariobroth:

In Super Mario Odyssey, the Odyssey gains a balloon instead of a sail upon completion of Bowser’s Kingdom during the story, when at least 124 total Power Moons are obtained. The balloon becomes slightly larger with each further Power Moon deposited into the Odyssey, up to a maximum of 999. After completing the story, the player can purchase unlimited numbers of Power Moons at stores for 100 coins each.

Thus, it is possible to deposit 875 Power Moons at once into the Odyssey by finishing the game with the minimum 124 Moons, and then buying the rest without using the Odyssey during this time. The resulting cutscene lasts 1 minute and 16 seconds as all Moons are deposited, and the balloon inflates in the most drastic manner possible from the smallest size to the biggest size instantly, as shown in the footage.
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