Index: ps/trunk/binaries/data/mods/public/simulation/ai/petra/chatHelper.js
===================================================================
--- ps/trunk/binaries/data/mods/public/simulation/ai/petra/chatHelper.js
+++ ps/trunk/binaries/data/mods/public/simulation/ai/petra/chatHelper.js
@@ -132,6 +132,15 @@
 	}
 };
 
+PETRA.emergencyMessages = {
+	"enter": [
+		markForTranslation("My armies failed while defending my empire. Please honor our alliance and send help!")
+	],
+	"exit": [
+		markForTranslation("My empire regained its old strength, now it is time to seek revenge together!")
+	]
+};
+
 PETRA.chatLaunchAttack = function(gameState, player, type)
 {
 	Engine.PostCommand(PlayerID, {
@@ -234,3 +243,12 @@
 		"parameters": { "_player_": player }
 	});
 };
+
+PETRA.chatEmergency = function(gameState, enable)
+{
+	Engine.PostCommand(PlayerID, {
+		"type": "aichat",
+		"message": "/allies " + pickRandom(this.emergencyMessages[enable ? "enter" : "exit"]),
+		"translateMessage": true
+	});
+};
Index: ps/trunk/binaries/data/mods/public/simulation/ai/petra/config.js
===================================================================
--- ps/trunk/binaries/data/mods/public/simulation/ai/petra/config.js
+++ ps/trunk/binaries/data/mods/public/simulation/ai/petra/config.js
@@ -175,6 +175,33 @@
 		"Market/InternationalBonus",
 		"Player/sharedDropsites"
 	];
+
+	this.criticalPopulationFactors = [
+		0.8,
+		0.8,
+		0.7,
+		0.6,
+		0.5,
+		0.35
+	];
+
+	this.criticalStructureFactors = [
+		0.8,
+		0.8,
+		0.7,
+		0.6,
+		0.5,
+		0.35
+	];
+
+	this.criticalRootFactors = [
+		0.8,
+		0.8,
+		0.67,
+		0.5,
+		0.35,
+		0.2
+	];
 };
 
 PETRA.Config.prototype.setConfig = function(gameState)
@@ -287,6 +314,12 @@
 	if (this.difficulty < PETRA.DIFFICULTY_EASY)
 		this.Economy.workPhase3 = Infinity;	// prevent the phasing to city phase
 
+	this.emergencyValues = {
+		"population": this.criticalPopulationFactors[this.difficulty],
+		"structures": this.criticalStructureFactors[this.difficulty],
+		"roots": this.criticalRootFactors[this.difficulty],
+	};
+
 	if (this.debug < 2)
 		return;
 	API3.warn(" >>>  Petra bot: personality = " + uneval(this.personality));
Index: ps/trunk/binaries/data/mods/public/simulation/ai/petra/emergencyManager.js
===================================================================
--- ps/trunk/binaries/data/mods/public/simulation/ai/petra/emergencyManager.js
+++ ps/trunk/binaries/data/mods/public/simulation/ai/petra/emergencyManager.js
@@ -0,0 +1,93 @@
+/**
+ * Checks for emergencies and acts accordingly
+ */
+PETRA.EmergencyManager = function(Config)
+{
+	this.Config = Config;
+	this.referencePopulation = 0;
+	this.referenceStructureCount = 0;
+	this.numRoots = 0;
+	this.hasEmergency = false;
+};
+
+PETRA.EmergencyManager.prototype.init = function(gameState)
+{
+	this.referencePopulation = gameState.getPopulation();
+	this.referenceStructureCount = gameState.getOwnStructures().length;
+	this.numRoots = this.rootCount(gameState);
+};
+
+PETRA.EmergencyManager.prototype.update = function(gameState)
+{
+	if (this.hasEmergency)
+	{
+		this.emergencyUpdate(gameState);
+		return;
+	}
+	const pop = gameState.getPopulation();
+	const nStructures = gameState.getOwnStructures().length;
+	const nRoots = this.rootCount(gameState);
+	const factors = this.Config.emergencyValues;
+	if (((pop / this.referencePopulation) < factors.population || pop == 0) &&
+		((nStructures / this.referenceStructureCount) < factors.structures || nStructures == 0))
+		this.setEmergency(gameState, true);
+	else if ((nRoots / this.numRoots) <= factors.roots || (nRoots == 0 && this.numRoots != 0))
+		this.setEmergency(gameState, true);
+
+	if (pop > this.referencePopulation || this.hasEmergency)
+		this.referencePopulation = pop;
+	if (nStructures > this.referenceStructureCount || this.hasEmergency)
+		this.referenceStructureCount = nStructures;
+	if (nRoots > this.numRoots || this.hasEmergency)
+		this.numRoots = nRoots;
+};
+
+PETRA.EmergencyManager.prototype.emergencyUpdate = function(gameState)
+{
+	const pop = gameState.getPopulation();
+	const nStructures = gameState.getOwnStructures().length;
+	const nRoots = this.rootCount(gameState);
+	const factors = this.Config.emergencyValues;
+
+	if ((pop > this.referencePopulation * 1.2 &&
+		nStructures > this.referenceStructureCount * 1.2) ||
+		nRoots > this.numRoots)
+	{
+		this.setEmergency(gameState, false);
+		this.referencePopulation = pop;
+		this.referenceStructureCount = nStructures;
+		this.numRoots = nRoots;
+	}
+};
+
+PETRA.EmergencyManager.prototype.rootCount = function(gameState)
+{
+	let roots = 0;
+	gameState.getOwnStructures().toEntityArray().forEach(ent => {
+		if (ent?.get("TerritoryInfluence")?.Root === "true")
+			roots++;
+	});
+	return roots;
+};
+
+PETRA.EmergencyManager.prototype.setEmergency = function(gameState, enable)
+{
+	this.hasEmergency = enable;
+	PETRA.chatEmergency(gameState, enable);
+};
+
+PETRA.EmergencyManager.prototype.Serialize = function()
+{
+	return {
+		"referencePopulation": this.referencePopulation,
+		"referenceStructureCount": this.referenceStructureCount,
+		"numRoots": this.numRoots,
+		"hasEmergency": this.hasEmergency
+	};
+};
+
+PETRA.EmergencyManager.prototype.Deserialize = function(data)
+{
+	for (const key in data)
+		this[key] = data[key];
+};
Index: ps/trunk/binaries/data/mods/public/simulation/ai/petra/headquarters.js
===================================================================
--- ps/trunk/binaries/data/mods/public/simulation/ai/petra/headquarters.js
+++ ps/trunk/binaries/data/mods/public/simulation/ai/petra/headquarters.js
@@ -44,6 +44,7 @@
 	this.diplomacyManager = new PETRA.DiplomacyManager(this.Config);
 	this.garrisonManager = new PETRA.GarrisonManager(this.Config);
 	this.victoryManager = new PETRA.VictoryManager(this.Config);
+	this.emergencyManager = new PETRA.EmergencyManager(this.Config);
 
 	this.capturableTargets = new Map();
 	this.capturableTargetsTime = 0;
@@ -66,6 +67,7 @@
 	this.treasures.registerUpdates();
 	this.currentPhase = gameState.currentPhase();
 	this.decayingStructures = new Set();
+	this.emergencyManager.init(gameState);
 };
 
 /**
@@ -2190,6 +2192,7 @@
 PETRA.HQ.prototype.update = function(gameState, queues, events)
 {
 	Engine.ProfileStart("Headquarters update");
+	this.emergencyManager.update(gameState);
 	this.turnCache = {};
 	this.territoryMap = PETRA.createTerritoryMap(gameState);
 	this.canBarter = gameState.getOwnEntitiesByClass("Market", true).filter(API3.Filters.isBuilt()).hasEntities();
@@ -2337,6 +2340,7 @@
 		API3.warn(" diplomacyManager " + uneval(this.diplomacyManager.Serialize()));
 		API3.warn(" garrisonManager " + uneval(this.garrisonManager.Serialize()));
 		API3.warn(" victoryManager " + uneval(this.victoryManager.Serialize()));
+		API3.warn(" emergencyManager " + uneval(this.emergencyManager.Serialize()));
 	}
 
 	return {
@@ -2352,6 +2356,7 @@
 		"diplomacyManager": this.diplomacyManager.Serialize(),
 		"garrisonManager": this.garrisonManager.Serialize(),
 		"victoryManager": this.victoryManager.Serialize(),
+		"emergencyManager": this.emergencyManager.Serialize(),
 	};
 };
 
@@ -2395,4 +2400,7 @@
 
 	this.victoryManager = new PETRA.VictoryManager(this.Config);
 	this.victoryManager.Deserialize(data.victoryManager);
+
+	this.emergencyManager = new PETRA.EmergencyManager(this.Config);
+	this.emergencyManager.Deserialize(data.emergencyManager);
 };