Texas Ranger: Old Rangers Die Hard: A Western Adventure (Texas Ranger Captain Bates #12)
Ash Lingam

The Tonkawa scouts, Tuc and Potak, hire on with the captain to track two evil killers who are killing innocent families and burning homes across the state. They embark on a journey across Texas and into The Oklahoma Territories.
Life on the reservations is hard, and food is scarce. As the tribes attempt to scratch out a living on drought-ridden and plague-infested land, a handful of greedy ranchers and Indian agents scheme to deprive them of the necessities of life. The once proud Indians are starving.
A different type of Texas Ranger takes chase and holds no quarter. After a personal tragedy Capt. Bates is a changed man and wreaks the wrath at will. He ignores the law and all he had stood for in the past.