A lot of people seem to have trouble sometimes beating the final boss, especially with Knuckles. Well, here's a strategy that will work for every character. First, chase Robotnik and go all the way to the right side of the screen until you can't go any further. You should be facing right, now slightly tap left twice. As the giant Robot Robotnik rises, hit him under the back twice. He will now walk forward. As he's walking, keep walking forward staying close enough to his leg. Don't touch the leg just stay close to it. When he stops, align you're character so their toes are touching the nut on the heel of the giant robot. Don't get too close or you'll die. Just have about 1/4 of your character's shoe touching the nut. As he starts flying up into the air hit him three times. Now, go stand all the way to the far right and face left and spin dash in place. As the robot is about to land, spin dash out of the way to the left side of the screen and just stay there avoiding his spike arms he throws. After he throws both arms, go to the middle pillar and stand on the left side of it, facing left and spin dash in place. When the robot is about to land again, spin dash out of the way and stand all the way on the left side to avoid those mini bomb robots he throws. He'll only throw two then start walking forward. Now, just walk forward as he walks staying close to his leg. As he stops again to fly up into the air, align your character's toes so they touch the nut on the heel of the robot and just hit him three times as he flys up. The pattern is the same from then on, so just repeat.
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 Go all the way to the right side of the screen until you can't go further and slightly tap left twice.
 As the robot rises, quickly hit him twice.
 Walk forward with the robot staying close to his leg.
 When he stops, align your character so they touch the nut on the robot's heel with their toes.
 As he flys up, hit him three times.
 Stand all the way on the right side of the screen, facing left and spin dash in place. Then spin dash out of the way to the left when the robot is about to land.
 Stand all the way to the left side of the screen to avoid the robot's arms. The arms won't reach you if stand as far as possible.
 After he throws both arms, stand on the left side of the middle pillar, facing left and spin dashing in place. Then, spin dash out of the way to the left as the robot lands.
 Stay all the way to the left to avoid the bomb robots he throws. They won't hit you if you stand all the way to the left.
 The pattern is the same from here on. He'll start walking forward, so you walk with him staying close to his leg.
 You know what to do. He'll stop, so you align your character so they touch that nut with their toes.
 Hit him as he goes up. Then, repeat the pattern over starting from step 6 until you beat him. It takes twelve hits to beat the boss.
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