In the opening and ending sequences of Super Mario World, the evil dinosaur crushes a Cave Person's car and attempts to eat Luigi, who is saved just in time by a vine-riding Oogtar. They are both voiced by Dan Hennessey, who also voices Bully Koopa and Rockman.
In "Party Line", the evil dinosaur appears near the beginning of the episode. It approaches Mario, Luigi, Yoshi, and Princess Toadstool; the latter comments that he looks hungry. It walks past them when they hide behind a rock.
It returns later in the episode, rampaging through Dome City while the Cave People are distracted by their telephones. It is about to eat Oogtar, but when Mario tugs its tail, it chases him instead. Mario briefly winds it when he is flung from a vine. The evil dinosaur lunges at Mario afterward but misses. It chews up several coins that Mario pelts at it, then throws one back at Mario's head, dizzying him. Mario uses a Starman to clamp the evil dinosaur's snout shut and launch it spinning like a tornado into space. It is last seen hurtling through a group of Caterpillars.
"Mama Luigi" shows that Luigi and Yoshi had met the evil dinosaur before. It and its teal friend, also a Tyrannosaurus rex, confronted them with intent to eat Yoshi. The dinosaurs ultimately could not reach their prey once Luigi jumped across a river of lava.