Easiest, cheapest method to knock out any level Rex is simply build 1 stone foundation,3 walls and 2 doorframes(no reinforced doors needed)....place the foundation down and the 3 walls in a U shape on the foundation then in the gap put 1 doorframe and the other doorframe on top....Then run up to the Rex tickle its balls and once u have Agro make a dash for your contraption run through the doorframe....Spin around, go into crouch and start firing tranq darts at it through the door frame( don't worry it won't be able to bite you as the doorframes are 2 walls high) This works on gigas too but go 3 wall high on door frames and use metal instead of stone. Hope this helps fresh spawns :)))

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