Of Turtles and Stones and Mary Bones

Of Turtles and Stones and Mary Bones is issue 6 of the TMNT Adventures, and was published in October 1989.

Storyline
Jess Harley in the Deep American South bayou steals what he doesn't know is the Turnstone from Mary Bones, according to rumors a swampwitch. He travels to New York City in an attempt to sell it. Mary Bones tracks him into town, and takes back the Turnstone and uses it to transform Jess Harley into Leatherhead. Shredder tricks Leatherhead into believing the turtles work with Mary Bones. The turtles defeat Shredder, Bebop and Rocksteady in fight but Leatherhead ends up lost.