Toy Story Toons: Partysaurus Rex is a 2012 Pixar animated short film directed by Mark Walsh. It will be first screened in theaters ahead of Finding Nemo 3D. Partysaurus Rex is the third short in the Toy Story Toons series, based on the characters from the Toy Story feature films. Toy Story's Rex, the green dinosaur, gets a chance to shed his party-pooper past in Disney•Pixar's new animated short.