Mysterious Dave Mather

(Wikipedia) Mysterious Dave Mather (born David Allen Mather) was an American lawman and gunfighter in the American Old West. His taciturn personality may earned him the nickname "Mysterious Dave." He was a lawman in Dodge City, Kansas and Las Vegas, New Mexico.
... Mather's early life is uncertain. He was in Dodge City, Kansas in 1872 where he and his brother Josiah may have reunited to become buffalo hunters. He was also reported to have partnered with Wyatt Earp in 1878 in a scheme to sell fake gold bricks in the town of Mobeetie, Texas. Continued