Some sources and resources on narcissistic personality disorder.
I don't know giant stories and characters but provide some tips of character building in general.
To create characters that seem to come from an ancient myth or legend, you write a myth or legend that seems to be ancient. It's all in the details.
45 Master Characters is a book of characters for writers to mix and match for their stories.
When done correctly, you can use first person in one chapter of your novel, and third person in the next chapter.