I missed the release of the Zork Trilogy in a single package back in the late eighties. The games have been in the collection for ages, but only as single entries.
The main attraction of the collection is an actual zorkmid coin minted for this release and this release alone. The presence of the coin is the reason why complete in box instances of this product pull in hefty bids on eBay.
The trilogy is obviously sold out long ago, and the coins thus limited in number.