I haven't been able to progress much due to 3 issues so far:
1) When you first encounter Zana in your party owner's atlas you will receive the missions to explore the corner regions of the atlas, but Zana won't join your hideout unless you find the first citadel in your hideout.
2) You will have a hard time finding a citadel in your own atlas if you have explored many maps through party play in your friend's atlas because you can't possibly keep track which maps you have explored on YOUR atlas and which not. At the moment I am sitting at 2 fully explored atlas regions but no citadel found. Probably need to rerun the maps I ran in group but don't remember which ones they were...
3) When you actually DO find a citadel in your own atlas but a party member enters the Zana portal first by mistake you don't get the unlock of the citadel on your atlas similar to when you find it in someone else's map.
These issues are decent proof that GGG didn't consider party play when making this new atlas mechanic so my advise for you is to abide their rule and do this sh*t solo until it may get fixed next league.
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