Index: binaries/data/mods/public/simulation/components/Player.js
===================================================================
--- binaries/data/mods/public/simulation/components/Player.js
+++ binaries/data/mods/public/simulation/components/Player.js
@@ -1,25 +1,33 @@
 function Player() {}
 
 Player.prototype.Schema =
-	"<element name='BarterMultiplier' a:help='Multipliers for barter prices.'>" +
-		"<interleave>" +
-			"<element name='Buy' a:help='Multipliers for the buy prices.'>" +
-				Resources.BuildSchema("positiveDecimal") +
-			"</element>" +
-			"<element name='Sell' a:help='Multipliers for the sell prices.'>" +
-				Resources.BuildSchema("positiveDecimal") +
-			"</element>" +
-		"</interleave>" +
-	"</element>" +
-	"<element name='SharedLosTech' a:help='Allies will share los when this technology is researched. Leave empty to never share LOS.'>" +
-		"<text/>" +
-	"</element>" +
-	"<element name='SharedDropsitesTech' a:help='Allies will share dropsites when this technology is researched. Leave empty to never share dropsites.'>" +
-		"<text/>" +
-	"</element>" +
-	"<element name='SpyCostMultiplier'>" +
-		"<ref name='nonNegativeDecimal'/>" +
-	"</element>";
+	"<optional>" +
+		"<element name='BarterMultiplier' a:help='Multipliers for barter prices.'>" +
+			"<interleave>" +
+				"<element name='Buy' a:help='Multipliers for the buy prices.'>" +
+					Resources.BuildSchema("positiveDecimal") +
+				"</element>" +
+				"<element name='Sell' a:help='Multipliers for the sell prices.'>" +
+					Resources.BuildSchema("positiveDecimal") +
+				"</element>" +
+			"</interleave>" +
+		"</element>" +
+	"</optional>" +
+	"<optional>" +
+		"<element name='SharedLosTech' a:help='Allies will share los when this technology is researched. Leave empty to never share LOS.'>" +
+			"<text/>" +
+		"</element>" +
+	"</optional>" +
+	"<optional>" +
+		"<element name='SharedDropsitesTech' a:help='Allies will share dropsites when this technology is researched. Leave empty to never share dropsites.'>" +
+			"<text/>" +
+		"</element>" +
+	"</optional>" +
+	"<optional>" +
+		"<element name='SpyCostMultiplier'>" +
+			"<ref name='nonNegativeDecimal'/>" +
+		"</element>" +
+	"</optional>";
 
 /**
  * Which units will be shown with special icons at the top.
@@ -43,6 +51,7 @@
 	this.state = "active"; // game state - one of "active", "defeated", "won"
 	this.diplomacy = [];	// array of diplomatic stances for this player with respect to other players (including gaia and self)
 	this.sharedDropsites = false;
+	this.sharedLos = false;
 	this.formations = [];
 	this.startCam = undefined;
 	this.controlAllUnits = false;
@@ -56,16 +65,14 @@
 	this.disabledTemplates = {};
 	this.disabledTechnologies = {};
 	this.startingTechnologies = [];
-	this.spyCostMultiplier = +this.template.SpyCostMultiplier;
-	this.barterMultiplier = {
-		"buy": clone(this.template.BarterMultiplier.Buy),
-		"sell": clone(this.template.BarterMultiplier.Sell)
-	};
+	this.spyCostMultiplier = +(this.template && this.template.SpyCostMultiplier || 1);
+	this.barterMultiplier = { "buy": {}, "sell": {} };
 
 	// Initial resources and trading goods probability in steps of 5
 	let resCodes = Resources.GetCodes();
 	let quotient = Math.floor(20 / resCodes.length);
 	let remainder = 20 % resCodes.length;
+	let hasBarterMultiplier = this.template && this.template.BarterMultiplier;
 	for (let i in resCodes)
 	{
 		let res = resCodes[i];
@@ -75,6 +82,8 @@
 			"goods":  res,
 			"proba": 5 * (quotient + (+i < remainder ? 1 : 0))
 		});
+		this.barterMultiplier.buy[res] = hasBarterMultiplier ? this.template.BarterMultiplier.Buy[res] : 1.0;
+		this.barterMultiplier.sell[res] = hasBarterMultiplier ? this.template.BarterMultiplier.Sell[res] : 1.0;
 	}
 };
 
@@ -131,7 +140,7 @@
 // Try reserving num population slots. Returns 0 on success or number of missing slots otherwise.
 Player.prototype.TryReservePopulationSlots = function(num)
 {
-	if (num != 0 && num > (this.GetPopulationLimit() - this.GetPopulationCount()))
+	if (num !== 0 && num > (this.GetPopulationLimit() - this.GetPopulationCount()))
 		return num - (this.GetPopulationLimit() - this.GetPopulationCount());
 
 	this.popUsed += num;
@@ -263,10 +272,10 @@
 	// Check if we can afford it all
 	var amountsNeeded = {};
 	for (var type in amounts)
-		if (this.resourceCount[type] != undefined && amounts[type] > this.resourceCount[type])
+		if (this.resourceCount[type] !== undefined && amounts[type] > this.resourceCount[type])
 			amountsNeeded[type] = amounts[type] - Math.floor(this.resourceCount[type]);
 
-	if (Object.keys(amountsNeeded).length == 0)
+	if (Object.keys(amountsNeeded).length === 0)
 		return undefined;
 	return amountsNeeded;
 };
@@ -278,9 +287,9 @@
 	// If we don't have enough resources, send a notification to the player
 	if (amountsNeeded)
 	{
-		var parameters = {};
-		var i = 0;
-		for (var type in amountsNeeded)
+		let parameters = {};
+		let i = 0;
+		for (let type in amountsNeeded)
 		{
 			++i;
 			parameters["resourceType"+i] = this.resourceNames[type];
@@ -320,7 +329,7 @@
 		return false;
 	}
 
-	for (var type in amounts)
+	for (let type in amounts)
 		this.resourceCount[type] -= amounts[type];
 
 	return true;
@@ -535,12 +544,13 @@
 	if (!cmpRangeManager || !cmpTechnologyManager)
 		return;
 
-	if (!cmpTechnologyManager.IsTechnologyResearched(this.template.SharedLosTech))
+	if (!this.template || !this.template.SharedLosTech || !cmpTechnologyManager.IsTechnologyResearched(this.template.SharedLosTech))
 	{
 		cmpRangeManager.SetSharedLos(this.playerID, [this.playerID]);
 		return;
 	}
 
+	this.sharedLos = true;
 	cmpRangeManager.SetSharedLos(this.playerID, this.GetMutualAllies());
 };
 
@@ -576,9 +586,9 @@
 
 Player.prototype.HasSharedLos = function()
 {
-	let cmpTechnologyManager = Engine.QueryInterface(this.entity, IID_TechnologyManager);
-	return cmpTechnologyManager && cmpTechnologyManager.IsTechnologyResearched(this.template.SharedLosTech);
+	return this.sharedLos;
 };
+
 Player.prototype.HasSharedDropsites = function()
 {
 	return this.sharedDropsites;
@@ -689,7 +699,7 @@
  */
 Player.prototype.IsNeutral = function(id)
 {
-	return this.diplomacy[id] == 0;
+	return this.diplomacy[id] === 0;
 };
 
 /**
@@ -746,9 +756,12 @@
 
 Player.prototype.OnResearchFinished = function(msg)
 {
-	if (msg.tech == this.template.SharedLosTech)
+	if (!this.template)
+		return;
+
+	if (this.template.SharedLosTech && msg.tech == this.template.SharedLosTech)
 		this.UpdateSharedLos();
-	else if (msg.tech == this.template.SharedDropsitesTech)
+	else if (this.template.SharedDropsitesTech && msg.tech == this.template.SharedDropsitesTech)
 		this.sharedDropsites = true;
 };
 
Index: binaries/data/mods/public/simulation/templates/special/player_gaia.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/special/player_gaia.xml
+++ binaries/data/mods/public/simulation/templates/special/player_gaia.xml
@@ -1,22 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <Entity>
-  <Player>
-    <SharedLosTech/>
-    <SharedDropsitesTech/>
-    <SpyCostMultiplier>1.0</SpyCostMultiplier>
-    <BarterMultiplier>
-      <Buy>
-        <food>1.0</food>
-        <wood>1.0</wood>
-        <stone>1.0</stone>
-        <metal>1.0</metal>
-      </Buy>
-      <Sell>
-        <food>1.0</food>
-        <wood>1.0</wood>
-        <stone>1.0</stone>
-        <metal>1.0</metal>
-      </Sell>
-    </BarterMultiplier>
-  </Player>
+  <Player/>
 </Entity>