If you punch, or feed a wild basilo the 3 mantas that spawned with it will each take 1 damage then become aggressive towards you same goes for ichthys and megs that get close
Basilosaurus
The Basilosaurus is a dolphin-like creature that primarily dwells along the shallow areas of the ocean. It has the ability to keep survivors warm or cool.

Player-written tips for taming, using, and fighting the Basilosaurus in ARK: Survival Ascended & Evolved.
If you wanna kill those demon jellyfish then I definitely recommend the basil because it is immune to their damage.
I find them in the waters between the Herbivore island and the lava cave peninsula
It doesn't get stung by jellyfish!! Go get you some biotoxin young lad!!
If you wanna tame a good level Whale without waste sources gathering a Bary, you can Just use a fast mount tho hit mantas around the Whale and then make they follow you tho a secure distance from Basilossaurus.
These guys take damage on asgard vanaheimm and jotumheim its annoying like I learned the hard way lol
If you want to kill the mantas around it get a tanky Barry and swim around them, lead them away from the basilosaurus and stun them.
The Basilosaurs can autonomously produce oil
This is by far one of the best water tames, has insane health regen and if you boost melee you can easily solo kill mosa and tuso alphas, good for jellyfish because cant be stunned. And keeps you warm underwater!
Managed to kill an alpha mosa with one! Wasn't max level at all, only lvl 100. They are badass, get decent health and you can survive most things! Also this is a biotoxin machine, taming has never been easier
So I was feeding it with the mantas still alive, that ended up with a couple of inactive specimen implants. When I finally got it, The mantas ended up killing the damned basilo. So, don't keep the manta's alive.
The easiest way to tame this whale is to bring a Baryonyx with ya to deal with the manta's and sharks and to wear scuba gear. Once the sharks and manta are dead just passive tame the whale with either prime meat or Theriz Kibble.
Watch for mantas
They are everywhere on the Center map
So, it turns out that killing a Basilo gives tons of Oil. This thought occured to me while I decided to be a jerk on my own Basilo. So go out there on your Ocean Mount and kill so many of your basilo’s cousins and rake in so much oil you’d get America Jealous
They are beautiful creatures but have little stamina.
I found a basilo quite near south zone it only had 2 low-level mantas and it tames fast I'm trying to get GPS to find the coordinates of where it is I'm gonna try to tame it after I get better weapons and a scuba diving set
I used to avoid the sea! Bit Feel so secure on one of these 10/10
Do HUNT BASILO pursuit on mobile to get an ascendant compound bow which is great for beating the boss. (I think pursuits are exclusive to mobile only)
This is the biggest deal you will ever own. Enjoy! Oh by the way: I hope you like mantas!
Wool owl