One of your normal tiles being overrun by an enemy unit: you temporarily lose access to work that tile, and surrounding tiles if you don't have units on them.
One of your citadel being overrun by an enemy unit: you permanently lose access to that tile and all surrounding tiles.
It's definitely worse having a citadel. A human would've replaced it with something else before the defending unit dies.
One of your citadel being overrun by an enemy unit: you permanently lose access to that tile and all surrounding tiles.
It's definitely worse having a citadel. A human would've replaced it with something else before the defending unit dies.