Two friends from my ls were hunting for the sky map last nite to use up their keys. They are a husband and wife so they do things together most of the time. After the first one got their map, they found the second one a bit later to have it "become an illusion and disappear".
I was surprised to find out that the fatigue applies after only opening one coffer and apparently applies across the party. I suggested to try zoning and waiting for it to wear off, but after about 45 minutes later and farming a new key the same thing happened. To which he replied "maybe my payment next month will be an illusion". Did they really implement this that poorly? Are your experiences the same? It would make more sense to me if the fatigue didn't set in until about 3-5 coffers, not 1.
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