Mysterious Awakening恐怖复苏

His ghostly eyes, what can they do except the domain? Is there really nothing more? But every ghost, if it becomes strong enough, will be able to use the domain. They must have some differences + their own unique abilities. But I didn't see it. Maybe this will be revealed later in the story, but I lost the desire to continue reading.

MC also seems to be perpetually weak. Yes, weak. Even when he completely subdued the headless shadow, he seemed to become very strong (especially compared to people), but for ghosts he still seems average.
In 300 chapters, the MC tried only twice to learn about the abilities of his ghosts, and somehow learn to use them, and learn something new about them. I’m already silent about the fact that he didn’t try to get new ghosts, given that his headless shadow can subjugate other ghosts and assimilate them (as I understand). But he didn't even try to hunt weaker ghosts.

So Coral who is a classmate of our mc, has a mother named Ocean and father named Beach? Is the author trolling? Does he mean corals are formed where an ocean and a beach meet?