Final (a) compactness, (b) specific central entropy, (c) iron core mass, and (d) binding energy above M₄ at the onset of core collapse as a function of the initial mass. The top axis shows the CO core mass at core helium exhaustion. Circles and crosses represent BH formation and explosions, respectively, according to the Ertl et al. (2016) criterion, while black and white colors indicate BH formation and explosions based on the Müller et al. (2016) SN model.