This is a constant topic since the launch of Diablo 3. We can see numerous threads talking about it every week or every time the server restarts or patch updates in the community. Blizzard replied the issue more than one time.
A player said he got 500% MF on MP5 and in patch 1.0.5 he had decent drops of legendary items. But now he got nothing.
Long time ago, community manager Vaeflare said there’s no relation between drop rates and account ID. Grimiku also said they did not change any of the drop rates. Players who get a lot of items with low MF just have good luck.
Since patch 1.0.6 did not change any of the drop rates I would say what you are experiencing is, unfortunately, simply a bad luck streak. :( I know it can be hard to believe after a very long run of previously great luck, but we truly didn’t lower the drop rates of Legendary items.
That said, our Bug Report forum would be a great place to post about those invisible monster attacks.
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