This category is a single segment run without resets. It is allowed to save, but cannot return to the file select screen for any reason. Thus, the Back in Time glitch is not allowed in this category. In addition, file setup doesn't really matter; just start with a blank Hero Mode file.
Your blank Hero Mode file needs at least one Ancient Flower (to repair Scrapper); if you want to do the upgrade to Quick Beetle, you'll need as well:
Ancient Cistern has two routes depending on the version you're running. Both possible routes follow.