How to tame a Rex.

1-you can outrun it eazily by using a raptor or a flying mount while keeping ahead of it and getting off and pelting it with tranq ammo of your choice,use dinosaurs that yih can use your tools and weapons on its back,a raptor or any others could work,even without a fast tame,you can outrun it with 120+-130 movement speed.

the second method is:

2-using a trap for the Rex,a trap that's wooden will work,but it's risky as if you use it on a high level Rex it will break the wood very eazily,I reccomend a stone trap,as it cannot damage stone structures,the trap that's 2 walls high and 3 walls in widgh should work,attract it's attention and lure it in into the trap and outrun it,once it's in the trap,pelt it with tranq ammo until it's knocked out,keep it asleep(it's torpor goes down quite slowly,but it has alot of torpor so bring alot of tranq ammo)use narcotics or biotoxin,use a soothing balm for high levels and in ark mobile also use a soothing balm,use raw prime meat or raw meat,for a high level I reccomend you use it's preferred choice of kibble,which is the quetzal kibble.

3-you've now got a Rex!now I will tell you it's advantages and disadvantages.

Advantages:it's base damage is 75(level1),and has a big hitbox when attacking,also it's hitbox is pretty big like I said,so you can land extra hits when a Dino is trying to get to you.

Disadvantages:it has poor stamina,slow swim speed,and kinda slow movement speed that's close to a raptors.

Fun fact:it's saddle is unlocked at level 74.