Cornerstone of the World

The cornerstone of the world isn't exactly a quest; but it's quest-like. It's a special floor tile found on the first level of the crypt, that allows you to transfer items between your single player characters. It does not work for multiplayer characters, don't waste your time (or items) trying it.

The Cornerstone's function is simple. Voyage to the stone with one character, drop whatever item you wish to transfer (copy) to another characters onto the stone, and save the game with the item still there. The next new game you create, with any single player character, on any difficulty level, will have that same item on the Cornerstone.

This isn't exactly an item transfer, it's a way to dupe items between characters, since the first character still has the item on the ground in their saved game. If you wish to play ethically, you'll leave it there, or drop it elsewhere in the dungeon once your second character gets their copy if it.

The Cornerstone is a way to transfer items, but it's not exactly convenient. After all, a character creating a new game has to get to the Cornerstone for the item to be there. (Joining a saved game won't work.) And to get to the top level of the Crypt, a character has to get the rune bomb, blow up the hive entrance, work through four levels of the hive, find the Defiler, get the cathedral map, portal back to town, walk to the cemetery, and then search the first level of the Crypt for the Worldstone room. Perhaps Sierra though this was a way to balance the item transfer/dupe option they were offering.

Cornerstone Lore

When items are dropped onto the Cornerstone, the following message is narrated.

And in the year of the golden light, it was so decreed that a great cathedral be raised. The cornerstone of this holy place was to be carved from the translucent stone Antyrael, named for the angel who shared his power with the Horadrim.

In the year of drawing shadows, the ground shook and the cathedral shattered and fell. As the building of catacombs and castles began and man stood against the ravages of the Sin War, the ruins were scavenged for their stones. And so it was that the cornerstone vanished from the eyes of man.

The stone was of this world -- and of all worlds -- as the light is both within all things and beyond all things. Light and unity are the products of this holy foundation, a unity of purpose and a unity of possession.

Interesting (or not) as you find this message and the other writings in the crypt, it and all the other plot and lore in Hellfire has to be considered non-canon, since the Blizzard North D1 and future D2 team were not directly involved in the production of Hellfire, except to veto various features they thought were too similar to what they were planning for Diablo II.

The Cornerstone of the World.