The dossier says they're passive to humans and only attack little fish THIS IS NOT TRUE THEY WILL EAT YOU AND THEY TEAM UP WITH ELECTROPHORUS TO KNOCK OUT YOUR MOUNT AND SHARE IN THE FEAST AFTERWARDS!!

THEY SPAWN IN GROUPS OF 2-3 AND CAN VERY WELL TAKE OUT A MEGALODON i put passive flee on mine and can't find it but the tribe menu says it didn't die plz brucey come backk

You're gonna need about three fiddy, then this beast will let you go.

This has to be the most terrifying creature on ark. I've tamed one and it still makes me piss my pants when i see it.

These are not "pleasuresaurs" as I soon found out =/

Long neck, tiny brain, infinite hatred, that alpha mosa was dying until these F'ers joined the bar fight and turned my victory into a massacre

Kill on sight, ask questions later, if you can't kill, F right off all the way to the surface because this spawn of spite COMMITS AND NEVER LETS GO

Any mobile players out there, there aren't any underwater caves so these guys are just commonly in the deep.

If you are being chased by a plesiosaur,then swim up to the surface.like the mosasaur,the plesiosaur does not swim over a certain depth limit and is never seen at the surface(bit weird since they need to breathe,right?)

Whoever said plesiosaurs are the quetzals of the ocean clearly has never tamed a mosasaur