Since Eggman's always striking back with another new trick up his sleeve, Sonic's usually got some help in the form of his supporting cast, including: Miles 'Tails' Prower (as in 'miles per hour'), a two-tailed fox kit serving as Sonic's trusty sidekick and Heli-Critter transport Knuckles the Echidna, Sonic's hot red foe-turned-friend with the physical power to match his namesake Amy Rose, his love-struck Fangirl with a Genki Girl attitude and a mallet you don't wanna mess with and the cavalcade of all the other friends and allies he's made over the years. 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.

Sonic 1 title screen sprites