I have successfully segregated those cards from the Dunwich Horror expansion that will work successfully only with the Arkham Board. I had to remove the following:
- The board, the Dunwich Horror token, and the Dunwich Horror cards
- All the Dunwich Horror specific location cards (28 total for Blasted Heath and Village Commons).
- Darke's Blessing, which can only be given due to a Dunwich Horror specific event.
- All the Mythos cards that opened Dunwich Horror gates (though I left Mythos cards that gave clues in Dunwich Horror locations). (30 total)
- All the outer world cards that either referred to Another Time or Lost Carcosa (32 cards)
- Gate tokens to Another Time or Lost Carcosa (4).
All the other items were integrated into my regular Arkham Horror box, in particular the rules as they have a good combined index.
-- Christopher Allen