Total mass (solid lines) and core mass (dotted lines) as a function of time for planets with final masses of 0.14, 1, 2, 5, and 10 M_X. For the lowest mass planet, we shut down accretion before it passes into the runaway gas accretion regime. The four more massive planets have a nearly identical core mass, which is not externally imposed but a natural consequence of the decrease of the capture radius and the increase of planetesimal ejection.