User blog comment:B214/Volume 21 info & spoilers/@comment-50.139.232.230-20160505222709/@comment-3435913-20160505230905

In volume 13 afterword, Ishibumi gave the fifth "hypothetical" arc the working title: "The God of Destruction Shiva Arc". Its not confirmed whether this will remain the title for this arc, but its the only one that exists as of right now.