The velocity of rise and the drag of a single vapor bubble collapsing in another immiscible liquid were measured experimentally. During the process of collapse, the dispersed-phase vapor bubble was transformed to a two-phase bubble with condensate accumulating at the rear of the two-phase bubble and vapor at its top. Such a configuration of a two-phase bubble is commonly known as a drobble. Experimental data for the six pairs of liquids covered a range of drobble (two-phase bubble) Reynolds numbers from 0.003 to 3,000. Two regimes of drobble movement were encountered. In the first regime (Re < 100), the drobble maintained its sphericity, and the observed drag was less than the solid-sphere drag predicted by the established solid sphere or Hadamard et al. fluid-sphere drag models. In the second regime, the drobble was deformed and oscillated; the observed drag departed suddenly from predictions of spherical models and increased with increasing Reynolds numbers. The critical Reynolds number covered a range from 100 to 1,000. Empirical models for drobble velocity and drag coefficient are derived.