Evolution of three planets in phase II with our default parameters (see Table 1) at 0.1 AU. The solid curve indicates the classical case, where the core grows indefinitely and the envelope is metal-free. In the dash-dotted and dashed lines, the growth of the core is limited to M_⊕ and 5 M_⊕, respectively.Accretion of nebular gas accelerates when the envelope becomes polluted. This leads to a smaller mass in metals at the onset of runaway accretion.