Foreign cards are cards that a player builds in his opponent's principality but that do not become the opponent's property.
A game turn is the period of time in which one of the players performs the game actions and actively intervenes. A game round is the immediate succession of two game turns, where both players alternately are the active player and the passive player.
It is not affected at all.
It is not affected at all. Each player mustn't observe the hand limit until the end of his turn.
Each unit whose text box shows the words "Unit - Hero" has hero status.
No.
During your turn, you can use most expansions as often as you like and can pay for (if payment is required). Some expansions of the Theme Sets can only be used once per turn, which is explicitly stated on the respective cards.
Yes.
No.
The card stays where it is and retains its effect. Requirements must only be met when playing the card; afterwards, they are irrelevant.
In most cases, immediately. Exceptions are explicitly stated on the cards or in the game rules.