Cronus Curses Zeus

This 'myth' isn't really a myth. All that is known about this is that, as Zeus was taking Cronus to Tartarus, Cronus cursed him, and said that just like Ouranos had cursed him (see the Murder of Ouranos), Cronus would make sure that one of Zeus' children would overthrow him. Prometheus later elaborates on this, saying that if Zeus has children with Themis, then one of his sons will eventually overthrow him.