The manipulation of the subpulse number, pulse delay, and pulse energy distribution of an ultrafast laser enables electron dynamics control by changing absorptions, excitations, ionizations, and recombinations of electrons, which can result in smaller, cleaner, and more controllable structures. This letter experimentally reveals that ablation sizes and recasts can be controlled by shaping femtosecond pulse trains to adjust transient localized electron dynamics, material properties, and corresponding phase change mechanisms.