Index: binaries/data/mods/public/gui/session/unit_actions.js
===================================================================
--- binaries/data/mods/public/gui/session/unit_actions.js
+++ binaries/data/mods/public/gui/session/unit_actions.js
@@ -1457,10 +1457,11 @@
 	if (entState.resourceSupply && entState.resourceSupply.killBeforeGather)
 		return translate("The entity has to be killed before it can be gathered from");
 
+	// Keep in sync with Controllability.js-component.
 	if (entState.capturePoints && entState.capturePoints[entState.player] < entState.maxCapturePoints / 2)
 		return translate("You cannot destroy this entity as you own less than half the capture points");
 
-	if (!entState.identity.canDelete)
+	if (entState.controllability && !entState.controllability.Deletable)
 		return translate("This entity is undeletable");
 
 	return false;
Index: binaries/data/mods/public/gui/session/unit_commands.js
===================================================================
--- binaries/data/mods/public/gui/session/unit_commands.js
+++ binaries/data/mods/public/gui/session/unit_commands.js
@@ -135,7 +135,10 @@
 	let playerStates = GetSimState().players;
 	let playerState = playerStates[Engine.GetPlayerID()];
 
-	if (g_IsObserver || entStates.every(entState => controlsPlayer(entState.player)))
+	// Always show selection.
+	setupUnitPanel("Selection", entStates, playerStates[entStates[0].player]);
+
+	if (g_IsObserver || entStates.every(entState => controlsPlayer(entState.player) && (!entState.controllability || entState.controllability.Controllable)))
 	{
 		for (let guiName of g_PanelsOrder)
 		{
Index: binaries/data/mods/public/simulation/components/Capturable.js
===================================================================
--- binaries/data/mods/public/simulation/components/Capturable.js
+++ binaries/data/mods/public/simulation/components/Capturable.js
@@ -160,6 +160,7 @@
 	Engine.PostMessage(this.entity, MT_CapturePointsChanged, { "capturePoints": this.cp });
 
 	var owner = cmpOwnership.GetOwner();
+
 	if (owner == INVALID_PLAYER || this.cp[owner] > 0)
 		return;
 
Index: binaries/data/mods/public/simulation/components/Controllability.js
===================================================================
--- /dev/null
+++ binaries/data/mods/public/simulation/components/Controllability.js
@@ -0,0 +1,65 @@
+class Controllability
+{
+	get Schema()
+	{
+		return "<a:help>Deals with the controllability of structures and units.</a:help>" +
+			"<a:example>" +
+				"<Controllable>true</Controllable>" +
+			"</a:example>" +
+			"<oneOrMore>" +
+				"<element>" +
+					"<anyName/>" +
+					"<data type='boolean'/>" +
+				"</element>" +
+			"</oneOrMore>";
+	}
+
+	/**
+	 * The initialisation of the component.
+	 */
+	Init()
+	{
+		this.controllability = {};
+		for (let entry in this.template)
+			this.controllability[entry] = this.template[entry] == "true";
+	}
+
+	/**
+	 * Whether the entity is controllable in some way.
+	 *
+	 * @param {string} type - The type to check controllability for.
+	 *
+	 * @return {boolean} - Whether the entity can be given the order.
+	 */
+	GetControllability(type)
+	{
+		return this.controllability;
+	}
+
+	/**
+	 * Whether the entity is controllable in some way.
+	 *
+	 * @param {string[]} types - The types to set the controllability for.
+	 * @param {boolean} bool - The boolean to set the controllability to.
+	 */
+	SetControllability(types, bool)
+	{
+		for (let type of types)
+			this.controllability[type] = bool;
+	}
+}
+
+Controllability.prototype.OnCapturePointsChanged = function(msg)
+{
+	let cmpOwnership = Engine.QueryInterface(this.entity, IID_Ownership);
+	if (!cmpOwnership)
+		return;
+
+	let owner = cmpOwnership.GetOwner();
+	let totalCapturePoints = msg.capturePoints.reduce((a, b) => a + b, 0);
+
+	// Keep in sync with gui/session/unit_actions.js.
+	this.SetControllability(["Deletable"], msg.capturePoints[owner] >= totalCapturePoints / 2);
+}
+
+Engine.RegisterComponentType(IID_Controllability, "Controllability", Controllability);
Index: binaries/data/mods/public/simulation/components/GuiInterface.js
===================================================================
--- binaries/data/mods/public/simulation/components/GuiInterface.js
+++ binaries/data/mods/public/simulation/components/GuiInterface.js
@@ -262,8 +262,7 @@
 			"rank": cmpIdentity.GetRank(),
 			"classes": cmpIdentity.GetClassesList(),
 			"visibleClasses": cmpIdentity.GetVisibleClassesList(),
-			"selectionGroupName": cmpIdentity.GetSelectionGroupName(),
-			"canDelete": !cmpIdentity.IsUndeletable()
+			"selectionGroupName": cmpIdentity.GetSelectionGroupName()
 		};
 
 	let cmpPosition = Engine.QueryInterface(ent, IID_Position);
@@ -286,6 +285,12 @@
 		ret.maxCapturePoints = cmpCapturable.GetMaxCapturePoints();
 	}
 
+	let cmpControllability = Engine.QueryInterface(ent, IID_Controllability);
+	if (cmpControllability)
+	{
+		ret.controllability = cmpControllability.GetControllability();
+	}
+
 	let cmpBuilder = Engine.QueryInterface(ent, IID_Builder);
 	if (cmpBuilder)
 		ret.builder = true;
Index: binaries/data/mods/public/simulation/components/Identity.js
===================================================================
--- binaries/data/mods/public/simulation/components/Identity.js
+++ binaries/data/mods/public/simulation/components/Identity.js
@@ -89,10 +89,7 @@
 		"<element name='RequiredTechnology' a:help='Optional name of a technology which must be researched before the entity can be produced.'>" +
 			"<text/>" +
 		"</element>" +
-	"</optional>" +
-	"<element name='Undeletable' a:help='Prevent players from deleting this entity.'>" +
-		"<data type='boolean'/>" +
-	"</element>";
+	"</optional>";
 
 Identity.prototype.Init = function()
 {
@@ -174,9 +171,4 @@
 	return this.template.GenericName;
 };
 
-Identity.prototype.IsUndeletable = function()
-{
-	return this.template.Undeletable == "true";
-};
-
 Engine.RegisterComponentType(IID_Identity, "Identity", Identity);
Index: binaries/data/mods/public/simulation/components/UnitAI.js
===================================================================
--- binaries/data/mods/public/simulation/components/UnitAI.js
+++ binaries/data/mods/public/simulation/components/UnitAI.js
@@ -187,8 +187,7 @@
 
 	// Called when being told to walk as part of a formation
 	"Order.FormationWalk": function(msg) {
-		// Let players move captured domestic animals around
-		if (this.IsAnimal() && !this.IsDomestic() || this.IsTurret())
+		if (this.IsTurret())
 		{
 			this.FinishOrder();
 			return;
@@ -234,13 +233,6 @@
 	// (these will switch the unit out of formation mode)
 
 	"Order.Stop": function(msg) {
-		// We have no control over non-domestic animals.
-		if (this.IsAnimal() && !this.IsDomestic())
-		{
-			this.FinishOrder();
-			return;
-		}
-
 		// Stop moving immediately.
 		this.StopMoving();
 		this.FinishOrder();
@@ -254,8 +246,7 @@
 	},
 
 	"Order.Walk": function(msg) {
-		// Let players move captured domestic animals around
-		if (this.IsAnimal() && !this.IsDomestic() || this.IsTurret())
+		if (this.IsTurret())
 		{
 			this.FinishOrder();
 			return;
@@ -280,8 +271,7 @@
 	},
 
 	"Order.WalkAndFight": function(msg) {
-		// Let players move captured domestic animals around
-		if (this.IsAnimal() && !this.IsDomestic() || this.IsTurret())
+		if (this.IsTurret())
 		{
 			this.FinishOrder();
 			return;
@@ -307,8 +297,7 @@
 
 
 	"Order.WalkToTarget": function(msg) {
-		// Let players move captured domestic animals around
-		if (this.IsAnimal() && !this.IsDomestic() || this.IsTurret())
+		if (this.IsTurret())
 		{
 			this.FinishOrder();
 			return;
@@ -455,7 +444,7 @@
 	},
 
 	"Order.Patrol": function(msg) {
-		if (this.IsAnimal() || this.IsTurret())
+		if (this.IsTurret())
 		{
 			this.FinishOrder();
 			return;
Index: binaries/data/mods/public/simulation/components/interfaces/Controllability.js
===================================================================
--- /dev/null
+++ binaries/data/mods/public/simulation/components/interfaces/Controllability.js
@@ -0,0 +1,6 @@
+Engine.RegisterInterface("Controllability");
+
+/**
+ * Message sent from Controllability component.
+ */
+Engine.RegisterMessageType("ControllabilityChanged");
Index: binaries/data/mods/public/simulation/components/tests/test_Capturable.js
===================================================================
--- binaries/data/mods/public/simulation/components/tests/test_Capturable.js
+++ binaries/data/mods/public/simulation/components/tests/test_Capturable.js
@@ -2,6 +2,7 @@
 Engine.LoadHelperScript("ValueModification.js");
 Engine.LoadComponentScript("interfaces/Auras.js");
 Engine.LoadComponentScript("interfaces/Capturable.js");
+Engine.LoadComponentScript("interfaces/Controllability.js");
 Engine.LoadComponentScript("interfaces/GarrisonHolder.js");
 Engine.LoadComponentScript("interfaces/StatisticsTracker.js");
 Engine.LoadComponentScript("interfaces/ModifiersManager.js");
Index: binaries/data/mods/public/simulation/components/tests/test_GuiInterface.js
===================================================================
--- binaries/data/mods/public/simulation/components/tests/test_GuiInterface.js
+++ binaries/data/mods/public/simulation/components/tests/test_GuiInterface.js
@@ -6,6 +6,7 @@
 Engine.LoadComponentScript("interfaces/Builder.js");
 Engine.LoadComponentScript("interfaces/Capturable.js");
 Engine.LoadComponentScript("interfaces/CeasefireManager.js");
+Engine.LoadComponentScript("interfaces/Controllability.js");
 Engine.LoadComponentScript("interfaces/Resistance.js");
 Engine.LoadComponentScript("interfaces/DeathDamage.js");
 Engine.LoadComponentScript("interfaces/EndGameManager.js");
@@ -543,7 +544,6 @@
 	GetRank: function() { return "foo"; },
 	GetSelectionGroupName: function() { return "Selection Group Name"; },
 	HasClass: function() { return true; },
-	IsUndeletable: function() { return false; }
 });
 
 AddMock(10, IID_Position, {
@@ -572,8 +572,7 @@
 		"rank": "foo",
 		"classes": ["class1", "class2"],
 		"visibleClasses": ["class3", "class4"],
-		"selectionGroupName": "Selection Group Name",
-		"canDelete": true
+		"selectionGroupName": "Selection Group Name"
 	},
 	"position": {x:1, y:2, z:3},
 	"hitpoints": 50,
Index: binaries/data/mods/public/simulation/helpers/Commands.js
===================================================================
--- binaries/data/mods/public/simulation/helpers/Commands.js
+++ binaries/data/mods/public/simulation/helpers/Commands.js
@@ -388,15 +388,11 @@
 	{
 		for (let ent of data.entities)
 		{
+			// Keep in sync with gui/session/unit_actions.js.
 			if (!data.controlAllUnits)
 			{
-				let cmpIdentity = Engine.QueryInterface(ent, IID_Identity);
-				if (cmpIdentity && cmpIdentity.IsUndeletable())
-					continue;
-
-				let cmpCapturable = QueryMiragedInterface(ent, IID_Capturable);
-				if (cmpCapturable &&
-				    cmpCapturable.GetCapturePoints()[player] < cmpCapturable.GetMaxCapturePoints() / 2)
+				let cmpControllability = Engine.QueryInterface(ent, IID_Controllability);
+				if (cmpControllability && !cmpControllability.GetControllability("Deletable"))
 					continue;
 
 				let cmpResourceSupply = QueryMiragedInterface(ent, IID_ResourceSupply);
@@ -867,6 +863,27 @@
 }
 
 /**
+ * Sends a GUI notification about entities that can't be controlled.
+ * @param {number} player - The player-ID of the player that needs to receive this message.
+ */
+function notifyOrderFailure(entity, player)
+{
+	let cmpIdentity = Engine.QueryInterface(entity, IID_Identity);
+	if (!cmpIdentity)
+		return;
+
+	let cmpGUIInterface = Engine.QueryInterface(SYSTEM_ENTITY, IID_GuiInterface);
+	cmpGUIInterface.PushNotification({
+		"type": "text",
+		"players": [player],
+		"message": sprintf(markForTranslation("Some %(unit)s can't be controlled."), {
+			"unit": cmpIdentity.GetGenericName()
+		}),
+		"translateMessage": true
+	});
+}
+
+/**
  * Get some information about the formations used by entities.
  * The entities must have a UnitAI component.
  */
@@ -1655,7 +1672,13 @@
  */
 function CanControlUnit(entity, player, controlAll)
 {
-	return IsOwnedByPlayer(player, entity) || controlAll;
+	let cmpControllability = Engine.QueryInterface(entity, IID_Controllability);
+	let CanBeControlled = IsOwnedByPlayer(player, entity) && (!cmpControllability || cmpControllability.GetControllability("Controllable")) || controlAll;
+
+	if (!CanBeControlled)
+		notifyOrderFailure(entity, player);
+
+	return CanBeControlled;
 }
 
 /**
Index: binaries/data/mods/public/simulation/templates/special/filter/mirage.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/special/filter/mirage.xml
+++ binaries/data/mods/public/simulation/templates/special/filter/mirage.xml
@@ -8,7 +8,6 @@
     <Tooltip merge=""/>
     <History merge=""/>
     <Icon merge=""/>
-    <Undeletable merge=""/>
   </Identity>
   <Minimap merge=""/>
   <Mirage replace=""/>
Index: binaries/data/mods/public/simulation/templates/special/filter/undeletable.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/special/filter/undeletable.xml
+++ binaries/data/mods/public/simulation/templates/special/filter/undeletable.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Entity merge="">
-  <Identity merge="">
-    <Undeletable>true</Undeletable>
-  </Identity>
+  <Controllability merge="">
+    <Deletable>false</Deletable>
+  </Controllability>
 </Entity>
Index: binaries/data/mods/public/simulation/templates/special/player/player.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/special/player/player.xml
+++ binaries/data/mods/public/simulation/templates/special/player/player.xml
@@ -63,7 +63,6 @@
     <Civ/>
     <GenericName>Player</GenericName>
     <Classes datatype="tokens">Player</Classes>
-    <Undeletable>true</Undeletable>
   </Identity>
   <Player>
     <BarterMultiplier>
Index: binaries/data/mods/public/simulation/templates/special/spy.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/special/spy.xml
+++ binaries/data/mods/public/simulation/templates/special/spy.xml
@@ -16,7 +16,6 @@
     <Classes datatype="tokens">Spy</Classes>
     <GenericName>Spy</GenericName>
     <RequiredTechnology>unlock_spies</RequiredTechnology>
-    <Undeletable>true</Undeletable>
   </Identity>
   <VisionSharing>
     <Bribable>false</Bribable>
Index: binaries/data/mods/public/simulation/templates/template_formation.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_formation.xml
+++ binaries/data/mods/public/simulation/templates/template_formation.xml
@@ -3,7 +3,6 @@
   <!--
   <Identity>
     <GenericName>Formation</GenericName>
-    <Undeletable>true</Undeletable>
   </Identity>
   <Selectable>
     <Overlay>
Index: binaries/data/mods/public/simulation/templates/template_gaia.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_gaia.xml
+++ binaries/data/mods/public/simulation/templates/template_gaia.xml
@@ -5,7 +5,6 @@
   <Identity>
     <Civ>gaia</Civ>
     <GenericName>Gaia</GenericName>
-    <Undeletable>true</Undeletable>
   </Identity>
   <Obstruction>
     <Active>true</Active>
Index: binaries/data/mods/public/simulation/templates/template_structure.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_structure.xml
+++ binaries/data/mods/public/simulation/templates/template_structure.xml
@@ -25,6 +25,11 @@
     <RegenRate>0.5</RegenRate>
     <GarrisonRegenRate>5.0</GarrisonRegenRate>
   </Capturable>
+  <Controllability>
+    <Controllable>true</Controllable>
+    <Deletable>true</Deletable>
+    <Unloadable>true</Unloadable>
+  </Controllability>
   <Cost>
     <Population>0</Population>
     <PopulationBonus>0</PopulationBonus>
@@ -60,7 +65,6 @@
     <Civ>gaia</Civ>
     <GenericName>Structure</GenericName>
     <Classes datatype="tokens">Structure</Classes>
-    <Undeletable>false</Undeletable>
   </Identity>
   <Loot>
     <xp>0</xp>
Index: binaries/data/mods/public/simulation/templates/template_unit.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit.xml
+++ binaries/data/mods/public/simulation/templates/template_unit.xml
@@ -6,6 +6,11 @@
     <Pierce>1</Pierce>
     <Crush>15</Crush>
   </Armour>
+  <Controllability>
+    <Controllable>true</Controllable>
+    <Deletable>true</Deletable>
+    <Unloadable>true</Unloadable>
+  </Controllability>
   <Cost>
     <Population>1</Population>
     <PopulationBonus>0</PopulationBonus>
@@ -52,7 +57,6 @@
       special/formations/battle_line
     </Formations>
     <Phenotype datatype="tokens">male</Phenotype>
-    <Undeletable>false</Undeletable>
   </Identity>
   <Looter/>
   <Minimap>
Index: binaries/data/mods/public/simulation/templates/template_unit_catafalque.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit_catafalque.xml
+++ binaries/data/mods/public/simulation/templates/template_unit_catafalque.xml
@@ -5,6 +5,9 @@
     <GarrisonRegenRate>0</GarrisonRegenRate>
     <RegenRate>10</RegenRate>
   </Capturable>
+  <Controllability>
+    <Deletable>false</Deletable>
+  </Controllability>
   <Cost disable=""/>
   <Footprint replace="">
     <Height>2.0</Height>
@@ -18,7 +21,6 @@
     <Icon>units/catafalque.png</Icon>
     <SelectionGroupName>template_unit_catafalque</SelectionGroupName>
     <Tooltip>A catafalque that holds the remains of a great leader.</Tooltip>
-    <Undeletable>true</Undeletable>
   </Identity>
   <Minimap>
     <Color r="148" g="0" b="211"/>
Index: binaries/data/mods/public/simulation/templates/template_wallset.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_wallset.xml
+++ binaries/data/mods/public/simulation/templates/template_wallset.xml
@@ -11,7 +11,6 @@
     <Icon>structures/wall.png</Icon>
     <RequiredTechnology>phase_town</RequiredTechnology>
     <Tooltip>Wall off your town for a stout defense.</Tooltip>
-    <Undeletable>true</Undeletable>
   </Identity>
   <Visibility>
     <RetainInFog>false</RetainInFog>