Question: What happened to Chris after he returned to his world? Did he become an adult again, or did he remain a child?
We Can See the Light! - S1-E41
Question: Why was Eggman controlling the moon in order to con people into buying the sunshine balls he invented? Was he doing it to get rich?
Answer: No, he doesn't need the money. He was doing it to try to paint himself as the hero. Make it look like only he could save the the light and painting Sonic as a villain for destroying it.
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So what if Eggman doesn't need the money. There are tons of people who don't need more, but still try to get richer.
But not Eggman. His goal isn't money in the series at all. He hardly even ever mentions it. He wants power, fame, and to rule the world. In fact, he comes from a world where money isn't exactly a thing or much of it. So he doesn't have that in his roots of desire, he wants power.
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