On ark the first thing I tamed was a level 1 Carbonemys. It was my favorite giant prehistorical turtle in the world, and it was my favorite thing in the entire game. Her name was Betty. I raised her all the way to level 18, and she was a good girl. May have been slow on land, may have been slow in the water, but when things got tight, her 879 health made up for everything. She was a walking tank. I once saw he kill an entire horde of piranha without getting to half health. But then, while riding my giant crocodile, I came across a pack of troodons. The surrounded me. Their leader, level 29, was no match for me. I tried to turn and run, but they surrounded chef the croc, and they attacked him from all sides. I wish his death was painless, but it wasn't. Then Betty sprang into action. Oh god, I wanted her to run away, but she was always so protective of me. She killed two of them, but the other five just started getting at her. Goddamn, I wish she would have just left..
I once tamed a level 125, and then I maxed it. I was a taming machine. Eventually, I had my first Rex! Yay! But when I turned it on Aggresive to kill some raptors, I titan came out of NOWHERE and killed it. Then it proceeded to kill everything. I ran for my life and escaped with my argy. Days later, I came back to see the remains. And there she was. My turtle. Bloody and beaten, but alive. I could see the titan in the distance, walking away. I then named the turtle Invincible and used her for every raid since she is still alive to this day. The end.
What ever you do, make sure it is alone while taming. I was a young level 30 lad back then when i stumbled across this turtle trapped between trees. My inexperienced mind thought "easy tame". I drew my tranq crossbow which my tribe mate had given me and shot once, shot twice, shot thrice. Then, to my horror i kid you not 5 level 80-120 turtles attacked my rear. I was now the one backed against the corner with only a ranged weapon. I drew a sword and started slashing, alas to no avail. The monsters killed me and i was put in a cage by my tribe for 3 houra because of my failures.