Captured Æmber is taken from an opponent’s Æmber pool and placed on a creature controlled by the capturing player. Captured Æmber is not part of a player’s Æmber pool and cannot be spent to forge keys.
When a creature with Æmber on it leaves play, the Æmber is placed in the opponent’s Æmber pool. Unless otherwise specified, Æmber is placed on the creature that captured it.
Related Topic: Playing Cards