I've become used to the idea that you don't use honorifics to talk about yourself (as explained in this answer). Of course I can imagine that you might do it as a joke, or when quoting or imitating someone else's speech. But in straightforward speech, is it true that no-one ever uses honorifics towards themselves? What about if the person is a king or person of particularly high rank?
I think that rather than use honorifics on oneself, people of great rank or importance talk to others and about themselves using a lower form of speech (like 해라체 or 반말).
One source I look to for this is the Bible. Even when God is speaking about Himself, he does not use honorifics. He uses 나는, 내가, 너희가, and so forth. These are all "low forms" of speech. God still shows his superiority and honor over others by how he speaks to them, it is just that the "-시" form is not how such is done in Korean. It would almost be like calling yourself "sir" in English. It would just sound weird, and even the president does not do it. (Or the king of England or whatever you want).
This is an interesting thing about Korean: You can explicitly elevate yourself over others by the form you use when speaking to them.
Kings in fiction, and kings in history sometimes used 짐 to refer to himself. This can be seen as elevated form of '나', but not necessarily. 짐 is also rare. The kings of Joseon dynasty used 나 primarily I believe. I've never seen or heard honorifics being used to explicitly elevate the speaker other than that.
But if "lowering the listener" counts as "elevating the speaker" relatively, then I'd say 해라체 would qualify as indirectly using honorifics to elevate the speaker.