This study explores the dynamics of the traditional toy Lato-Lato, consisting of two balls connected by a string whose midpoint is attached to a vertically oscillating support. When the support vibrates at certain frequencies and amplitudes, the system transitions from regular pendulum motion to collisions, causing the oscillation amplitude to grow significantly. Through precise experiments and motion analysis, we examine how vibration frequency, amplitude, and string length affect energy and momentum transfer. Finally, we propose a phase-adjustment method to optimize energy transfer efficiency, offering insights for future engineering applications.