>>714306542
I think all this timeline stuff was hammered out after 1-4 were made because the guidebooks for 2 say they thought the game took place in the 70s or 80s with a loose timeline, while nothing indicates Sh1 takes place before 2. 2 is also replite with endless anecdotes of various catastrophies, including multiple incidents of entire peoples just vanishing which seems to hint this kind of catastrophes keep happening.

Lot of hints the lake is somehow involved as well.

Could be something as simple the town and lake have just witnesses so much death and misery it left an impression on the area. Maybe it was a spirital place by the natives, and they revered it, but the catastrophies tainted the spiritual energy to be dark and malicious.