To kill it for my first time, I took my rifle and a bunch of bullets and attempted to kill it. I died 3 times before it finally died, each time grabbing my rifle again and trying and failing until it finally worked. A better way to kill, if no intention to tame at all, it to use narcotics on it until it passes out, and then kill it in its sleep. At that point it would be easy to tame, but it requires lots of narcotics to keep unconscious, so if supplies are limited, or just that your only intentions are to kill it, just keep attacking it with whatever weapon you have. This works at almost any level, as long as you have at least 8-15 narcotic arrows.

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