Mary is a works diesel who lives at Kahlville Works.
Mary is the versatile Works Diesel for the Kahlville Works, where Victor, Kevin, and Doc work at. She's very sympathetic towards the engines she helps out, and will always be willing to lend them a wheel. She's been equipped with newer tech that allows her to be fitted with a variety of tools to her front, including a plow, a bucket, and a special grapple, usually used for laying down railroad ties for track work.
Mary is not based on a specific prototype.
Mary is hot pink with turqoise stripes and a sky blue warning panel. She has a grey bufferbeam and four bright blue buffers. Her wheels are dark grey, and she has a gold bonnet on her front cab. Her front headlamp is purple as well.