I encountered an alpha raptor, pulled the ol' mountain trick on it (Basically just rub up to the side of a mountain and climb uphill, that way it can't climb up to you)

Tbh the mountain trick works on most things, I used it to kill a level 100+ (Pretty sure level 135) Therizinosaur or whatever it was called. Just make sure to bring lots of arrows. Oh, and if you have good aim you can get an achievement thing which gives you an ascendant bow.

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