They are mildly slow, but you might want to get on a rock and shoot it with tranq arrows, takes 2-5 arrows and make sure you have bio toxin on you. Takes a while for them to tame, the best thing to beat that time is to get a sleeping bag ( Not a simple bed!) And sleep in it. When you wake up shove a hundred bio toxins down it's throat, wait that three more minutes, and you got a stego.

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