I haven’t advanced to try to tame one of these guys, because my server has a glitch were I go god speed in water. Help. But, I have seen that they have manta allies that follow them, so good luck taming them.

But, it wouldn’t be a tip if I just said that. I believe if you have a flying mount, tapejara and Quetzal would work, because you can jump out at the water off your tapejara and shoot it with tranqs. For the Quetzal, it would just be to get off onto its platform saddle. (If it has one.)

Then, shoot it with tranqs until it goes unconscious. Get a group of ichys (or low level megs ) to attack the mantas, then drive them away from the basilosaurus. (kill the mantas if you prefer that method.) keep it unconscious by shooting it again, punching it, etc, until it has low food. Wait for it to wake up, (make sure you have a tracker on it, which you access via your inventory (it’s the dinosaur track with the plus sign next to it) so that you now where he/she is) but before that make sure there are no mantas around to come protected it. Then, feed it. (But, this is just an idea. This may not work. I am unsure, though.)