If you have enough metal;

Craft 4 metal billboards and one big bear trap.

Place down 3 of the billboards like this I_I and place the trap in the middle. Lure the rex into it, very easy and best to do on feet and then if he gets trapped, place the last billboard to close the cage.

Now you can take your time, knock it out or let it stay in there.

If the rex, somehow, gets nearly dead, I believe you can try to give it some corpses to eat and its HP will go up. :)

- ByNT

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