In Agile Docs, you can create a parent-child relationship between any issues. This means you can create higher level issues above Epics, make Tasks children of Stories and much more.
To create a custom issue hierarchy with Agile Docs:
1) Go to “Settings” and “Issues”
2) Select “Issue linking”
3) Scroll down to “Add New Link Type” and create a new link type with name “Agile Docs Parent”, outward link description “parent of” and inward link description “child of”
4) Open an issue you want to make a parent of child of another issue, select “Link Issue” and add the “parent of” link if you want to make it the parent of another issue or “child of” link if you want to make it the child of another issue
5) Open Agile Docs to view your new hierarchy