The entity has alternating Lock and Unlock buttons in the GUI, which can be used to force its gate open or closed (unlocked gates stay open if a player entity is adjacent, but close to deny entry to the enemy).

Gates are the weak point in a wall. They are more suseptable to crush attack. Not only do they allow your units to exit, they are possible points of entry by the enemy. Celts do not have gates.

Example:

        <Actions>
  		<Lock />
  	</Actions>

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