Smudger is a narrow gauge tank engine who used to work on the Mid Sodor Railway and was later turned into a generator due to his tendency to derail frequently for a while before being sold to the Crotoonian Hills Narrow Gauge Railway. Smudger was a complete show-off and often derailed, but refused to listen to advice. Duke warned him to be careful, but he took no notice until he was put in his place by being turned into a generator for a while. He was then sold to the Crotoonian Hills Narrow Gauge Railway to serve as a generator for a while. But when the workload began to pile up, he was given a chance to be really useful again, and was reconfigured into an engine. While he still shows up from time to time, he’s learned not to overdo it and to take care as he goes about his work.