You can kill it by using a Thylacoleo; the dino does a percentage of damages, so you need to hit it 20 times to kill. However, if you kill it with a Thylacoleo, you don't get exp. Bite it around 18/19 times, then finish it with a weapon. (Also, you can't spam bite it; you need to wait until the bleeding effect is gone, then bite it again)

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