Rotatatron

Rotatatron (ビッグボーイ), also known as the "Big Boy" by Doctor Eggman, is the name given to the giant robot fought in the boss stage of Tropical Resort in the Wii version of Sonic Colors. On Planet Wisp, this boss is shown to have an upgraded counterpart, Refreshinator.

History
After Sonic discovers Eggman is capturing Wisps for his own evil deeds, Eggman unleashes the Rotatatron to stop Sonic, but the boss is ultimately demolished. When destroyed, a part of Rotatron's arm becomes lodged in a part of Dr. Eggman's Incredible Interstellar Amusement Park; and in the end of the story, the arm causes Eggman's giant mind control cannon to backfire.

Battle
This boss fight is rather simple, as he only takes three hits to defeat, and attacks by clamping his hands on the circular arena. The weak point of the giant contraption is its large yellow eye located at the center off its body, which can be hit by a Homing Attack, when the eye is fully open. One platform has a capsule containing a Cyan Wisp which can be used to attack either his eye or his arms to deal double damage. If the Cyan Laser attacks Rotatatron's arms, then the laser runs through the arms like an electric current and strikes the eye. After the eye is hit three times by a Homing Attack or a Cyan Laser, the robot is destroyed, showering Sonic with Rings, and then the player is ranked.

Video(s)
Sonic Colors - Rotatatron Boss Fight

Trivia

 * Rotatatron is the name of the boss according to the Sonic Colors Prima Guide ﻿and the Sonic Colors Original Soundtrack - ViViD SOUND X HiBRiD COLORS. In-game, however, Eggman calls it the "Big Boy", probably in reference to its Japanese name.
 * Despite being replaced with Globotron in the Nintendo DS version of Sonic Colors, Rotatatron makes a cameo in the second act of Tropical Resort on the Nintendo DS version as the Ferris wheel that chases Sonic towards the end of the act.