Semi-weird + multiple heroines + semi-omnipotent protagonist + creatures from the Book of Mountains and Seas
Ordinary strange invasions, but they are all different creatures from the Book of Mountains and Seas. What if Song Tan, the traveler who wrote the book of mountains and seas, obtained a book of strange books about mountains and seas, how would he face it? What about this world?
The fire of the candle dragon has turned into darkness, the Suzaku has died, and only a book of strange records of mountains and seas is left, which finally serves as a carrier to record the past.
(There may be a small amount of Cthulhu elements. If you don't like it, you can find other masterpieces)
[Because this author is relatively cheap, I have to wait until 150,000 words before recommending]