If a card ability allows a player to play or use another card (or to fight or to reap with a card), the chosen card may belong to any house unless the ability specifically states otherwise.
When using a card via a card ability, all other restrictions and requirements of using the card (such as exhausting to reap, fight, or resolve its “Action:” ability) must be observed, or the card cannot be used.
Players can only use cards they control, unless a card ability specifically states otherwise.
—KeyForge Master Rulebook v18.3, February 2026