It's a f*cking jellyfish.
In my whole time in the Dark Sea, a jellyfish monster is the last creature in the ocean I would think that would become a boss here. Although there was a chance, I didn't see any of it even when I reached the highest waves of monsters back then. Even the supposed wave 20 is not a jellyfish monster.
But seeing our wave 20 jellyfish monster, made me wonder whether the enemies spawned here in the Dark Sea were not completely scripted by the laws of nature.
"Manato, I am quite sure wave 20 is not a jellyfish... Should we engage or should we retreat?" Pandora asked, ready to accept the decision I will make.
"Although I am not entirely sure about this guy, we will have to try it out. Check things out and see whether we can defeat it. If not, we retreat. That is our only option."