If you are planning on doing anything involving water prepare to despise these flat horrors. They can out swim you. They can swarm you. They can act friendly and once you turn your back eat your tame. Beware.
If caught in open water by a manta fight don't flee. If you have a spear or pike swim up as it gets close. This keeps you above it attack area and puts you in striking range. The manta is slower moving up and down in the water.
The manta is quite dangerous, as it's attacks can punch straight through armour, even flak. They are very fast and unless you have lots of oxygen and speed, you will not escape. Just poke your head underwater and look left and right before crossing the sea. It's like a road, but worse, because roads don't have angry stingrays, very large sharks and/or killer piranha
So, yesterday I tamed my first Megalodon (around lvl 105), I went outside of our base to test it. Killed a bunch of other megalodons and mantas. That was pretty easy. Went back to base. An hour later, my megalodon died...ONE OF THE FUCKING MANTAS FOLLOWED ME AND ENTERED VERY SNEAKY IN MY BASE AND KILLED MY FUCKING MEGALODON. It was a lvl 5 so it took a fucking hour to kill my megalodon. Those are bitches. Update: I tamed another megalodon today. Lvl 200. Fuck mantas.
Found a basilosaurus once being follow by two of these mad little pancakes I accidentally hit the basil and got swarmed by life 50 of the mad pancakes I screamed before they killed me they killed my level 100 meg they are like a swat team for the basil I started crying then my mum walked in and asked why I was crying I explained then she gave me the look
First you want to cuddle with it but you see another "What ever,twice the fun." you think. But then "A third, no fourth, no sixth, no tenth, MY SARCO!!! NO I DIED AND LOST A JOURNEY MAN CROSSBOW AND MY SCUBA GEAR." Looks at level of mantas /level 4/ "Lil shit."