Systems for actuating at least two engine valves comprise a valve bridge operatively connected to the at least two engine valves and having a hydraulically-actuated lost motion component. The lost motion component comprises a lost motion check valve disposed therein. A rocker arm has a motion receiving end configured to receive valve actuation motions from a valve actuation motion source and a motion imparting end for conveying the valve actuation motions and hydraulic fluid to the lost motion component. The rocker arm is in fluid communication with a hydraulic fluid supply. The systems also comprise an accumulator in fluid communication with the hydraulic fluid supply and disposed upstream of the lost motion check valve. In all embodiments, a fluid supply check valve may be disposed upstream of the accumulator and configured to prevent flow of hydraulic fluid from the accumulator back to the hydraulic fluid supply.