In this follow up expansion to the original Shadowrift, Archfiends pits the heroes of legend directly against the master of each faction bent on destroying the city of Haven. In addition to the monsters faced during the course of a regular game, the heroes must now contend with the Archfiend's scheming and personal onslaught, and once the Shadowrifts are sealed the heroes must defeat this terrifying villain in mortal combat.

Archfiends expands the cooperative deckbuilding game Shadowrift. The Archfiend will have its own special deck that allows it to wade into the middle of the heroes and wreck all their plans for saving the town. There are six Archfiend decks - one keyed to each of the six monster factions from the Shadowrift base game. Will you emerge from the battle victorious? Or will the Archfiend see you bloody, battered and beaten?

• Archfiends: The expansion adds six Archfiends, one for each of the monster factions in the base game. Each Archfiend has its own 30-card deck with special abilities.
• New Objective: In the base game, players can win by either sealing all the rifts or by building eight walls. With the Archfiends expansion, sealing the rifts is only the first step; players must then defeat the Archfiend in combat to win.
• Hero Titles: The expansion also includes "Hero Title" cards that heroes can claim for performing certain tasks, giving them an effect to use once per round after a monster is killed.