During step 2 of each turn, the active player must choose one of the three houses indicated by their Archon identity card, if able. Some card abilities may restrict a player’s house choice. The active player must make their house choice obvious to their opponent, such as by saying the choice aloud.
If a player has gained control of a card that does not belong to one of their three houses, that card’s house becomes an eligible choice for that player while the player retains control of the card.
A card’s house can be modified by card abilities. Unless otherwise specified, if an ability modifies the house of a card, the card belongs only to the house specified in the ability. If multiple abilities modify the house of a card, the most recent effect takes precedence.
If there is no legal choice of house, the player plays the turn with no active house.
If the active player is instructed they “must choose” two (or more) houses, the active player may choose any one of those houses.