I know it's not a direct sequel. But people are saying it take place after The Writer. How is that possible? Don't want to spoil the ending of The Writer.

Did you play The Writer?

yes

The thing he starts writing at the end of The Writer, this is it.

Did I find a manuscript that mentioned American Nightmare taking place

@JusticeCat said:

Did I find a manuscript that mentioned American Nightmare taking place

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2 years after Alice was released from Couldron Lake? or at least referring to a time where 2 years had passed since.

Yes, this takes place that long after the first Alan Wake. There are mentions of what other characters have been doing since.

The actual gameplay starts with you watching the cabin sink into the water.