Scram
Ryu had already expected this. This first barrier was nothing more than a checkpoint, one probably 100% of the geniuses who dared to enter would pass.
The only reason he had triggered the appearance of the anglerfish was because he had almost "stepped out of bounds". And the reason he had felt that the anglerfish's attack was weaker than it should have been was precisely because it was. It wasn't trying to kill him, it was trying to knock him back in bounds.
However, that didn't mean that things would continue to stay the same. There would almost certainly be problems soon. It was just that for Ryu the trouble came instantly.
'False Sky God, much more manageable.'
Ryu was already quickly deducing how this place would work, and he also realized that the density of the Rotten Sea was probably another test.