only thing you need to do to unlock island santuary is finish the 6.0 main story. unlocks in old sharlayan near market area talk to the clueless crier. in morabay docks talk to boldin to get to your island. after arriving you will be sent on to do a tutorial to understand the basics. after that you are basically on your own. content unlocks as you rank up your island and expand your hideaway. build your workshops and craft handicrafts to gain experience and currency called seafarer coweries or blues. you need these to expand your hideaway so dont spend them till your island is done.
shoutout to my youtube member and subscriber ayman for the intro to this series.
https://store.playstation.com/#!/tid=CUSA00572_00
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thanks, was very helpful
My pleasure 🙏🏻
🙂❤❤