Obsidian Forge

From Archon Arcana
Obsidian Forge • Dis • Artifact • Uncommon • Action: Destroy any number of friendly creatures. You may forge a key at +6Aember icon current cost, reduced by 1Aember icon for each creature destroyed this way. If you forge a key this way, destroy Obsidian Forge. • Artist: Hans Krill • Card Number: WC (093), MM (025)

Obsidian Forge
WC 093
MM 025
Artist: Hans Krill

FFG Rulings

  • No. If they are not “destroyed this way” they do not reduce the key cost.

    Source: Rulebook
If I use Obsidian Forge (WC 025)'s action and choose to sacrifice one of my creatures that has a ward on it, will that creature reduce the cost to forge that key?
No. If they are not “destroyed this way” they do not reduce the key cost.

Source: Rulebook

Commentary

Obsidian Forge specifically looks at whether a creature was successfully sacrificed to reduce the key cost. If a card was prevented from being sacrificed or leaving play by an effect like Ward, the creature's ward token will be removed, but it will not reduce the cost to forge.

When resolving the ability of Obsidian Forge, "any number" can be treated as zero.

Source: Play (step)