The Ghost of King Boom Boo in the Old Castle - S1-E19
Other mistake: When Chris says, "We'll be out of camera range," Tails has his legs crossed, but his tails have disappeared.
Other mistake: Tails automatically knows Cosmo's name even before she introduces herself later on (English Dub version only).
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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