One-Eyed Bart is a "character" in the 1995 and 2010 Disney/Pixar movies Toy Story and Toy Story 3. He is western outlaw played by Mr. Potato Head.
At the beginning of Toy Story, he holds toys hostages and threatens to have Bo Peep's sheep be splattered. Woody arrives and already sees through the criminal's disguise. Bart calls for his attack dog (who activates his force field). Woody summons the dinosaur (portrayed by Rex). Woody places Bart in prison (Molly's bed). Molly drools on Potato Head and strikes him, causing his parts to fall off. Andy picks up Woody and says (to him) "You saved the day again, Woody."
Toy Story 3
In Toy Story 3, Bart is seen stealing money from a train. He then shouts "Ha, ha, ha! Money, money, money!", Similar to the scene in the first film, He is confronted again by Woody. But this time Bart's wife, One-Eyed Betty, comes in and attacks Woody causing him to fall off the train, but is saved by Bullseye and Jessie. Bart picks up a remote to trigger an explosion to destroy the train tracks. He and Betty jump into a Corvette and leave. The train falls before Buzz Lightyear activates his jetpack and flies upward to catch the train. Bart and Betty ride the Corvette until it is wrecked by Buzz's wrist laser. Bart calls for his attack dog (who activates his force field). Jessie summons the dinosaur (portrayed by Rex). Dr. Porkchop's spaceship appears and pulls the criminals in. Porkchop orders Monkeys to restrain the heroes. But then, Buzz uses his laser to bring the ship down, ending the scenario.