Robo-Tug is a villainous tugboat with two smokestack, a cab-back hydraulic grabber and a construction hat. He is the main villain in Theodore and the Magic Harbor. He is the biggest, stronger and toughest tugboat in the Big Harbor, which is bigger, stronger and tougher than George.
He is a large, powerful tug. Behind his cab mounted in front of fake smokestack is a hydraulic crane arm with a giant metal claw. He wanted to destroy the harmony on the Big Harbour.
- His character resembles Diesel 10 from Thomas and Friends.