Scabbers (Rat Form)

Scabbers, appearing as Ron Weasley's loyal but aging rat, is unremarkable in the early books until his true identity as the Animagus Peter Pettigrew is dramatically revealed in Harry Potter and the Prisoner of Azkaban. This exposure transforms him from a mere pet into a central figure in the series' backstory, linking him to the Potters' betrayal and Sirius Black's wrongful imprisonment. Post-revelation, Scabbers vanishes from the narrative, his rat form serving as a pivotal plot device that reshapes understandings of loyalty and deception across the saga.