In both cases, it's merely Gameplay And Story Segregation - the developers just lacked the time or drive to make different-colored sprites for all of the Emeralds.) (There are only two games where this is not the case - Sonic Spinball, where none of them are green (they're all blue instead), and Sonic Battle, where all of them are green. note Incidentally, despite being called 'Emeralds', only one of them is green. Naturally, the free-spirited Sonic doesn't approve of Eggman's ambitions, and Eggman really hates that hedgehog for expressing said disapproval through scheme-thwarting time and time again, so the series follows wherever the endless conflict between fat man and kinetic Funny Animal will take them next. Eggman- a mustached Mad Scientist with a big girth, bigger robot army and an even bigger ego, and a life goal of using his scientific know-how (with unique power sources like the Chaos Emeralds being a plus) to achieve world domination. This platforming plethora of ring-collecting and badnik-charging stars the titular Sonic the Hedgehog, a real cool blue dude with Super Speed and a knack for taking whatever thrill rides he can find. Sega's flagship franchise, one of the most popular video game properties of all time, and one that is both famous and infamous.
