Brian Clipper (born 1985) is a super-speedster, known first as Fleetfeet and then as the second Darkhorse. He is extremely competent in terms of the application of his wide-ranging speed powers, and thus cocky to a fault.
See also: Journey Into... # 3.
As Fleetfeet, Clipper operated in Washington State. Definitely more of a day-time bright-colours hero than a renegade vigilante, he worked closely with the police department and national government to combat any number of weird and super-powerful threats while attending college and living with his girlfriend, Daphne.
When one of his college professors, manipulated by Fleetfeet's nemesis the Gorgon, came close to uncovering Clipper's secret identity, Clipper faked Fleetfeet's death. With Fleetfeet dead and Clipper still alive, he had proved that the two were not one and the same.
Phillip Whaley, the original Darkhorse, passed his mantle onto the now-married Clipper and hooked him up with a government stipend. Brian and Daphne moved just outside of Jolt City-- much to the chagrin of Jolt City's resident costumed adventurer, the Green Knight (Martin Rock).
When Martin Rock escaped from Earbox, Clipper attempted to apprehend him. He sustained massive injuries when Martin used his powers against him. First in traction, then in a wheel-chair, he has over the course of the following year been committed to intensive physical therapy.
Brian and Daphne briefly became nudists. It is suspected that this is the result of some lingering hypnotic suggestion implanted by the Gorgon.
As Fleetfeet: Journey Into... # 3.
As Darkhorse: Jolt City # 4, 9-11, 13.