Edge 1: The Loner by George G. Gilman

Edge 1
The Loner 
by George G. Gilman (Terry Harknett)
1972 New English Library

Josiah Hedges returns from the Civil War to find his brother has been tortured and killed. Where this would merely send other western heroes on a path of vengeance, Hedges has a complete psychotic break and goes on a murder spree. Can't exactly say his victims were innocent, but there's not even a pretense of self defense.

The series remains at least as violent, though with somewhat more motive. This one ends with him ending up a Sherriff of a border town - not sure if Harknett knew where the series was going at this point.

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