If you're lucky, you can find one of these alone. I would recommend targeting one that is alone, unless it is too high of a level or too low. Therefore you don't have to worry about Carnotaurus trying to kill you. Kill off anything ot might try to pick a fight with, like mammoths (you can use the prime meat from them to tame it). It takes a good amount of arrows so best if you use tranq darts instead. Just be careful of its roaring because there could be Carnos nearby.

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