Index: binaries/data/mods/public/simulation/ai/petra/defenseManager.js
===================================================================
--- binaries/data/mods/public/simulation/ai/petra/defenseManager.js
+++ binaries/data/mods/public/simulation/ai/petra/defenseManager.js
@@ -69,26 +69,17 @@
 {
 	if (type == "default")
 	{
-		// Try to add it to an existing army.
 		for (let army of this.armies)
 			if (army.getType() == type && army.addFoe(gameState, entityID))
-				return;	// over
+				return;
 	}
 
-	// Create a new army for it.
-	let army = new PETRA.DefenseArmy(gameState, [entityID], type);
-
-	this.armies.push(army);
+	this.armies.push(new PETRA.DefenseArmy(gameState, [entityID], type));
 };
 
 PETRA.DefenseManager.prototype.getArmy = function(partOfArmy)
 {
-	// Find the army corresponding to this ID partOfArmy.
-	for (let army of this.armies)
-		if (army.ID == partOfArmy)
-			return army;
-
-	return undefined;
+	return this.armies.find(army => army.ID == partOfArmy);
 };
 
 PETRA.DefenseManager.prototype.isDangerous = function(gameState, entity)