I think one of the easiest ways to get black pearls is to get a mosa keep leveling health and damage about 15K hp and 300-400 damage. Then find and destroy the alpha mosa. (you might want a saddle with good armor) Bring a Megalodon or other creature to the squid, once he is grabbed very quickly swim to the squid and feed the pearls you got from the alpha. That is how I have tamed my two squids and it works very well. (I play mobile so I don’t know in it will work on pc or xbox)

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