Index: binaries/data/mods/public/simulation/ai/common-api/entity.js
===================================================================
--- binaries/data/mods/public/simulation/ai/common-api/entity.js
+++ binaries/data/mods/public/simulation/ai/common-api/entity.js
@@ -98,18 +98,22 @@
 		return 0;
 	},
 
-	"cost": function(productionQueue) {
+	"cost": function(trainer) {
 		if (!this.get("Cost"))
 			return {};
 
-		let ret = {};
-		for (let type in this.get("Cost/Resources"))
+		const ret = {};
+		for (const type in this.get("Cost/Resources"))
+		{
 			ret[type] = +this.get("Cost/Resources/" + type);
+			if (trainer)
+				ret[type] *= trainer.trainCostMultiplier(type);
+		}
 		return ret;
 	},
 
-	"costSum": function(productionQueue) {
-		let cost = this.cost(productionQueue);
+	"costSum": function(trainer) {
+		const cost = this.cost(trainer);
 		if (!cost)
 			return 0;
 		let ret = 0;
@@ -122,6 +126,10 @@
 		return +(this.get("Researcher/TechCostMultiplier/"+type) || 1);
 	},
 
+	"trainCostMultiplier": function(type) {
+		return +(this.get("Trainer/TrainCostMultiplier/" + type) || 1);
+	},
+
 	/**
 	 * Returns { "max": max, "min": min } or undefined if no obstruction.
 	 * max: radius of the outer circle surrounding this entity's obstruction shape
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
@@ -361,7 +361,8 @@
 	const cmpTrainer = Engine.QueryInterface(ent, IID_Trainer);
 	if (cmpTrainer)
 		ret.trainer = {
-			"entities": cmpTrainer.GetEntitiesList()
+			"entities": cmpTrainer.GetEntitiesList(),
+			"trainCostMultiplier": cmpTrainer.GetTrainCostMultiplier()
 		};
 
 	let cmpTrader = Engine.QueryInterface(ent, IID_Trader);
Index: binaries/data/mods/public/simulation/components/Trainer.js
===================================================================
--- binaries/data/mods/public/simulation/components/Trainer.js
+++ binaries/data/mods/public/simulation/components/Trainer.js
@@ -20,6 +20,11 @@
 			"</attribute>" +
 			"<text/>" +
 		"</element>" +
+	"</optional>" +
+    "<optional>" +
+	"<element name='TrainCostMultiplier' a:help='Multiplier to modify resources cost and train time of entities with.'>" +
+		Resources.BuildSchema("nonNegativeDecimal", ["time"]) +
+		"</element>" +
 	"</optional>";
 
 /**