I am also wondering what the criteria are for more guilds. I came back after a while AFK and saw that I had 1 at city #1 and another at city #2 on island #2, and used them. Then I saw island #3 was open, and I can pay for quest leveling there, but have 0 guild halls I can open in either city, meaning the island is useless to me. Are open guilds shared universally? When are they earned? Game either doesn't explain this or buries the explanation.
Maybe I'm just slow, but is there any particular reason why you can't return quests unless you're on quest mode? I ask because a lot of the time when I'm finishing the last quest in a zone, I want to move to another zone, but in order to return the quest I'm basically forced to begin fighting something else immediately after since that's what quest mode does. Minor point, but yeah.
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