Steer clear, my Carno who could 1v1 Rexs got taken out by one of these.

i threw a spear at a group of these guys, then my sarco went to kill them and I watched in horror as she flew through the air dead, now all I do is kill every last one of these guys

Never go near it with your Dino, it will kill you, your Dino, your friends, your family, the guy down the street, some guy over in Africa, all while they won't do a thing to attack it.

I lost my level 305 giga just earlier today to these guys, I hate them.

So, I tamed a mosasaur after that I encountered THESE monsters known as Cnidaria. Here’s a little tip if it throws you off your mount swim down and kill the jellyfish

Use a basilosaurus to fight them. Since all their attacks involve electricity unlike the electric eels which can bite, they are doing no damage to the basilosaurus. Just spam the attack button and don’t forget to harvest their body for toxin too!

Up to 15 tentacles grow from each corner of the bell and can reach 10 feet in length. Each tentacle has about 5,000 stinging cells, which are triggered not by touch but by the presence of a chemical on the outer layer of its prey.

I found an invincible one:( :( :(

If you are reading this it seems your underwater adventure came to a shocking conclusion.