Tribes that have tamed a Basilosaurus can make use of it for a safer encounter with most underwater creatures as well as its ability to produce oil that can be used for crafting.

What does a pegomastax do in Ark?

The Pegomastax steals a random item from a survivor's inventory. If wild, the Pegomastax must either be killed, tranquilized, or tamed in order to retrieve the stolen item.

What is a Basilosaurus in Ark survival evolved?

The Basilosaurus is not actually a reptile despite its name, but a whale or cetacean. It has a long snake-like body that undulates through the seas of the ARK like the sea serpents of folklore and its head is like a crocodile, full of sharp teeth.