The Neo-Soviet marine biomods
Classified as a category 4 threat, the Elib is somewhere between a vampire lord and Godzilla for limits of escalation. Yes, I would consider using a nuclear device to kill just one. I am that sure that I want it dead.
The small coastal town of Her-Desh has vanished - the bay where it once stood is now unspoiled countryside. Moreover, the locals claim to have never heard of the place. Perhaps the Priests of the local Temple can shed some light on the mystery...