First built a structure of rock walls and climate it with the help of stairs and break stairs from downward rex can't climb and hit it with crossbow or gun to knock it out.

Second use spike trap to cover it so one dino will able to attack it then use narcotics over 64 to make it more unconscious over night till it's hunguer is 59 percent and use meat to tame it

An easy way to knock one out with a friend.

Take your flyer and carry your friend, fly high enough so that the Rex can’t reach you or your friend, but also so that they can shoot at the Rex. Get your friend to shoot at them with whatever tranq, I did it with about 8 tranq arrows and a normal bow but you might need more.

If you’re playing solo though I suggest leading the Rex under a rock ledge, land on the ledge and shoot at it till it gets knocked. Or you could just run at it and try to knock it fast but I’d rather play it the safe way.

Large and beefy, these lizards are known all around the community for one thing: BIG DAMAGE. Rexes will take out just about anything you want them to, only losing to the greatest creatures. Rexes aren’t rare either, if you know where to look. (Pro tip: the more north you go, the more rexes you might see!)

Uh I just discovered an extremely cruel way to gather large amounts of raw prime meat on mobile. I hatched a Rex egg and got twins, but after checking their stats I realised they were not the best (their dad tamed out at lvl 202 and their mom tamed out at lvl 209 but the babies were only lvl 201). I decided to kill them cuz I was running out of tame slots. Afterwards I ate their dead bodies with my wolf and found out that my wolf’s inventory is filled with raw prime meat. I immediately turned on my industrial grill and cooked all of it. The 2 baby Rex gave me a total of 128 raw prime meat... that’s like as much raw prime meat as an alpha raptor would drop from each one of the babies. So yeah if you really want easy raw prime meat and don’t care about being cruel you can try to get multiple breeding pairs of Rexes and kill their babies...

You’ll be fine with taming this as long have you have high ground, their roars don’t have any effect on you or other animals, so don’t worry about that. Bring about 150 tranq arrows and get onto a high rock (I couldn’t find one so I just stood on top of some random server players tower and shot at it from there) and just continuously shoot at it, then once it starts running you might have to get onto the ground and chase after it, still shooting at it, until it’s finally knocked out.

If you just so happened to be taming this thing in the chalk cliffs on valguero like me, make sure there are no armadillos or ankylos around the Rex , because if the Rex gets knocked next to a herd of them, they will all start to attack the unconscious Rex and all of your hard work goes down the drain. Their torpor goes down pretty slowly and I didn’t need any narcos, but I reccomend bringing a few just in case.