If you want to fight or knock one out, get up close and hope that it will then opt to use its melee rather than it's spines, as the latter will shred you in a matter of seconds. Trapping it with a bola is also a good method as it will be unable to turn its body to fire at you, but still be wary of it's AOE where it shakes and shoots spines in a small radius around it.

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