I've been swimming around vash. and have noticed there are 2 whale sharks (these are not actual world bosses, they dont drop loot but give you a achievement)
however there is another ?? mod named valskar she has 3.6million hp and is one of those long snakes.
I was wondering if they are bringing them back and if they drop loot or if others are for achievements. I cant find anything on valskar though =[