Archipelago Explorer

Track which IEs your alt has done:

/run local i={12590, 13099,13389,13095,13107,13111,13119,13396,13103};for _,j in ipairs(i) do local _,n,_,_,_,_,_,_,_,_,_,_,c=GetAchievementInfo(j); if (c) then print("\124cFF00FF00"..n); else DEFAULT_CHAT_FRAME:AddMessage("\124cFFFF0000"..n);end end

They have to be unique islands, so you'll have to wait for a weekly reset to put different islands on the rotation.

there are currently 8 different possible island 'locations', and for this achievement you need to have won Expeditions to 5 unique islands

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• Molten Cay
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• Whispering Reef
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• Verdant Wilds
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• Ungol Ruins
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• Rotting Mire
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• Dread Chain
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• Skittering Hollow
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as of the time of writing, it's week 2 of BfA and the fastest possible for anyone to complete this achievement, as each week there are only 3 unique islands available for Expeditions