Black-hole and neutron-star masses of Case A (panels a, d), Case B (panels b, e), and Case C (panels d, f) accretors as a function of the final CO core mass M_CO. The bottom row is a zoom into the NS-mass regime. The NS and BH masses of the single-star models are shown for comparison and accretor models with f_acc = 0.25, 0.75, and 2.00 are connected by lines to guide the eye. Systems likely experiencing SN fallback are marked by grey boxes and models that should have experienced LBV-like mass loss are indicated by crosses (cf. Sect. 2.1).