Stephen Myler

The Black Rider - Tom O'Leary - expert in side arms (Colt 1860 Model), rifle (Henry 1860) and stock whip. Black stallion horse - Emerald. Tom is a wanderer of justice - with a dark secret - he is not of this planet. Sent by distant galaxy to examine the people of earth and see if they are worth invading. Hidden away in a cave is his spaceship, temporary home, with advanced technology. A computer chip in the horses brain allows him to communicate and direct it.
His weapons look like normal cowboy arms of the time, but with the touch of a tiny button can turn into something more.