Sanctum is a two-player digital collectible card game, played online against human opponents.
[4] The virtual "collectible cards" include common, uncommon, and rare, with different powers, in-game functions and artwork.
They do not exist as actual physical cards (with the exception of a few that were distributed by Digital Addiction for promotional purposes) but they are owned and traded in an online account, and are played solely within the virtual environment of Sanctum.
The rest of the squares of the grid are randomly assigned one of the basic terrain types: plains, forest, desert, water, swampland or mountains.
As with many fantasy games, spell-casting in Sanctum is constrained by a limited resource called Mana.
[9] Rosenbaum's World Fantasy Award-nominated story "A Siege of Cranes" is set in the game's universe.
Faced with the prospect of the game vanishing, several players created the non-profit company Nioga ("Non-profit International Online Gaming Association") and acquired the game-related assets of Digital Addiction with the intent of keeping it running for its players.
[11] The Nioga members intended to donate all game profits (generated through the sale of virtual cards) to charity.