I think it would be super cool if the mod author would add an underwater cave entrance that led to a massive underground cave that consisted of only extinction stuff. Unless this is very well hidden I thought this is what was meant when they said there was Atlantis under water. Also when I mean huge I mean large enough to fill underneath one of the islands in the map already like they have done with a lot of the caves in the game. Like an entirely new map under the map similar to the different levels in abberation. Doesnt necessarily need to be extinction, just thought that may be a cool idea