Board Thread:General Discussion/@comment-24674051-20140422161814/@comment-1773585-20140424120323

Rumple said that it was prophesized that Cora's daughter would cast the curse. Zelena's time-travelling antics would not really affect him, so instead of coming to Cora with a deal about her first born, he would've trained Zelena directly and then that witch would've casted the curse.