If you have a pteranadon, 4 stone Gates and a large bear trap with around 20-35 tranqs in a crossbow you can take it down. Imagine a square of Gates, except there's one missing and a L bear trap in the middle. You lure It from the side with the gate missing. when it gets stuck, cover up the last gate and you can fire away. You can use whatever you want for taming. You can also do this with the rex.

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