I saw this thing roaming around my camp in singleplayer once (in a area near where the southern coast and the southern jungle meet) and decided to approach it, BIG MISTAKE! It attacks you, and I suggest if you ever do what I did , you have a medium amount of stamina to run, because I was running away from the Therizinosaurus and it hit me while I was running. Best thing to do is build a spiked wooden wall and wait for it to die.

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