Integrated engine brake

An integrated engine brake assembly may include a valve that forces oil circulating through an engine to flow to an exhaust rocker arm when an engine brake lever is operated, a bridge that forms an interval with a pair of first and second exhaust valves installed on a combustion chamber, an internal oil flow path which supplies the oil flowing toward the exhaust rocker arm to the bridge through an internal space of the exhaust rocker arm, and along which the oil is supplied to the bridge and brings the bridge into contact with the pair of first and second exhaust valves under pressure, and a protrusion lifting up the exhaust rocker arm at a compression top dead center so that the pair of first and second exhaust valves are pressed and opened forcibly by the bridge, and the bridge is pressed by seesaw movement of the exhaust rocker arm.