Morning Atlassian-ites(?) 
I've been searching for a solution but could not find a compelling answer in the forums and online so far so, at the risk of asking a question that may have been answered but I failed to see it, I want to define a specific ticket structure: Epic->Feature->UserStory->Task. Alas, the only ticket I can use as a parent is Epic. I picked my brain to see how I could add that structure but... all points to it not being supported... is that the case?
I mean, the hierarchy of tickets is a baseline to lock the structure and not have tickets that end up where they do not belong and I fail to see how I can implement that...
Any insights?
Oh, yeah, I don't have access to plugins from Marketplace... this is my client's Jira and I can't add/remove plugins willy-nilly 