Chaos Zero: simple boss with sonic. his weakness is his brain so that is all you need to aim for. use the homing attack on his brain. after 2 times, he will jump on a pole and start punching at you from a long distance. run around so it doesn't hit you. when Chaos jumps down, hit the brain.
Egg Hornet: here's Eggman. he shots missles so just dodge them. then he dives at you. dodge this. when that happens hit him while he is in the ground.
same for Tails.
Chaos Two: use Knuckles gliding (or Super Heat attack if you have it) to hit the brain. when Chaos turns into a giant ball, you just run away until it goes back to its original state. that is basically all there is to beating Chaos Two.
In this area Sonic, Tails, and Knuckles will be put against each other like so:
Sonic = Knuckles
Knuckles = Sonic
Tails = Knuckles
Chaos Four: now Chaos is a shark. use the lilly pads to avoid being in the water (which you really would like to avoid that). Chaos will swim up and hit the lilly pad you are on, so when he gets under you... move to another one. sometimes Chaos will do a flip causing a lot of lilly pads to sink. when Chaos surfaces, attack the brain with the homing attack or light speed attack if you have it.
with Knuckles, glide into the brain when yu can.
with Tails you just need to get close enough to hit the brain by jumping into it.
E-101 Beta: E-101 has more offensive power because it has 2 guns instead of 1. with E-102 Gamma, simple move around while targeting E-101. shoot E-101 until you win.
another fun match up game:
E-102 = Sonic
Sonic = E-102
Tails = E-102 Chaos Six: Big the Cat has the simplest boss in the world. i beat this boss in about 5 seconds(seriously). simple aim your fishing pole for Froggy. catch Froggy and you win. Chaos Six(for real this time): Chaos is a big scorpion now... how fun. Chaos will be trying to suck you up, shoot his body out in all directions, and try to hit you with its tail. Eggman is trying to hit you with his freeze bots at the same time (leave it to Eggman to help you out). hit the freeze bots with a homing attack to make them fall. then pick them up and throw them into Chaos to freeze it. now homing attack it, or light speed attack for twice the damage. simple fight.
with Knuckles the boss is slightly harder because parts of the platforms are missing. but basically you do the same thing. freeze chaos, use either the gliding, punching, or for twice the damage the super heat attack.
Egg Walker: Eggman will shoot missles at you if you are far away from him. get under Eggmans machine. he will then start stomping shockwaves at you. hit all the legs that stomp so Eggman becomes vulnerable. hit Eggman. repeat.
Egg Viper: this fight starts pretty good. start off by running to one side of the platform to collect some rings. Eggman is going to try to shoot the crapp out of you so turn and run the other way. when Eggman stops moving and opens the cockpit, home attack him. now when you dodge everything he will shoot a big laser at you. then when the cockpit it open, you will need to homing attack the little spheres to reach him. after a little while he will destroy half of the battlefield. now it gets interesting. he will shoot two spin saws at you. jump ontop of them and hit Eggamn. repeat once more.
E-103 & E-104: defeat these two just the same way you defeated E-101. move around and shoot. they are easy.
E-105: now this one is a bit more challenging. run around and shoot all the guns and everything you can target. watch closely where you move so you dont kill yourself.
E-101 MK II: no this is one of the best bosses. perfect offense and good defense. wait until E-101 charges at you, dodge. then turn and shoot the robot in the back. that is basically all you need to do. when E-101 shoots missles, do your best to target and eliminate all of them. when it hovers up and starts charging shots, move around the outside of the platform to dodge them all.
Zero: if you are fast enough you won't really need to put up with the attacks from this robot. hit the robot into the electricity surging all around the platform. do that a few times and you win.
Perfect Chaos: basically just move towards Chaos as fast as you can to hit it three easy times. then three much harder times. Chaos will use about three different attacks. multi-blast basically shooting a dozen fire balls at you. twisters, it shoots three of them to get in your way. or it will shoot a mega beam seen in the cinimatic sequence before the fight. the fire balls are easy to dodge the first three hits, but the las three Chaos will take much better aim so be careful.