Awakening of the Past

The Protagonist Transforms into Cthulhu, and the Other Protagonists Feel Crushed by Cthulhu.

Are Any of the Protagonists from the Old Ones?

The protagonist travels through time and becomes the Old Ones, and knows that he is one of the Old Ones. Cthulhu

Old Ones Series

Old Ones Series

Are There Any Old Books in Which the Protagonist Is a God Who Cannot Be Seen, Cannot Be Spoken, and Cannot Die?

The main character's ability is speech. If you don't find this kind of book, I'll recommend something else! There's been a book shortage lately! ! !