That vile aggressive electric fish from Serious Sam: The First Encounter and Serious Sam: The Second Encounter . Replaces the dolphin, so that it can be seen at sea without any problems. Not dangerous.
But if you want it to become DEADLY dangerous, the readme says how to combine this mod with the ! script! Killer Sharks .
P.S. The difference from the previous version, which I posted in the summer, is in a fully automatic installation and a slightly tweaked texture.
P.S.S. There is something interesting in the folder Bonus . Have a good game!