I've been thinking of creating a simple mod that will add a check box in the Story Progression settings to control the spread of mermaids, much like the checkboxes for the other occults and the pets. I know there's already mods that can disable the spread of mermaids but none of them actually add a check box in the settings, which I think would be very useful. I haven't ever created a mod but I'm sure the story progression aspect won't be too difficult to figure out but what about adding the check box? Does the game even allow us to edit or override the settings menu?