diff --git a/binaries/data/mods/public/maps/random/rmgen/group.js b/binaries/data/mods/public/maps/random/rmgen/group.js
new file mode 100644
index 0000000000..13688d9676
--- /dev/null
+++ b/binaries/data/mods/public/maps/random/rmgen/group.js
@@ -0,0 +1,73 @@
+/**
+ * A Group tests if a set of entities specified in the constructor can be placed and
+ * potentially places some of them (typically all or none).
+ *
+ * The location is defined by the x and z property of the Group instance and can be modified externally.
+ * The Group is free to determine whether, where exactly and how many entities to place.
+ *
+ * The Constraint to test against and the future owner of the entities are passed by the caller.
+ * Typically Groups are called from createObjectGroup with the location set in the constructor or
+ * from createObjectGroups that randomizes the x and z property of the Group before calling place.
+ */
+
+/**
+ * Places all of the given Objects.
+ *
+ * @param objects - An array of Objects, for instance SimpleObjects.
+ * @param avoidSelf - Objects will not overlap.
+ * @param tileClass - Optional TileClass that tiles with placed entities are marked with.
+ * @param x, z - The location the group is placed around. Can be omitted if the x and z properties are set externally.
+ */
+function SimpleGroup(objects, avoidSelf = false, tileClass = undefined, x = -1, z = -1)
+{
+	this.objects = objects;
+	this.tileClass = tileClass;
+	this.avoidSelf = avoidSelf;
+	this.x = x;
+	this.z = z;
+}
+
+SimpleGroup.prototype.place = function(player, constraint)
+{
+	let resultObjs = [];
+
+	// Test if the Objects can be placed at the given location
+	// Place none of them if one can't be placed.
+	for (let object of this.objects)
+	{
+		let objs = object.place(this.x, this.z, player, this.avoidSelf, constraint);
+
+		if (objs === undefined)
+			return undefined;
+
+		resultObjs = resultObjs.concat(objs);
+	}
+
+	// Add all objects to the map
+	for (let obj of resultObjs)
+	{
+		let x = obj.position.x / CELL_SIZE;
+		let z = obj.position.z / CELL_SIZE;
+
+		if (g_Map.validT(x, z))
+			g_Map.addObject(obj);
+
+		if (this.tileClass !== undefined)
+			getTileClass(this.tileClass).add(Math.floor(x), Math.floor(z));
+	}
+
+	return resultObjs;
+};
+
+/**
+ * Randomly choses one of the given Objects and places it just like the SimpleGroup.
+ */
+function RandomGroup(objects, avoidSelf = false, tileClass = undefined, x = -1, z = -1)
+{
+	this.simpleGroup = new SimpleGroup([pickRandom(objects)], avoidSelf, tileClass, x, z);
+}
+
+RandomGroup.prototype.place = function(player, constraint)
+{
+	return this.simpleGroup.place(player, constraint);
+};
diff --git a/binaries/data/mods/public/maps/random/rmgen/placer.js b/binaries/data/mods/public/maps/random/rmgen/placer.js
index ee92123599..c478e7f0d4 100644
--- a/binaries/data/mods/public/maps/random/rmgen/placer.js
+++ b/binaries/data/mods/public/maps/random/rmgen/placer.js
@@ -483,93 +483,3 @@ RandomObject.prototype.place = function(cx, cz, player, avoidSelf, constraint, m
 
 	return resultObjs;
 };
-
-/////////////////////////////////////////////////////////////////////////////////////////
-//	SimpleGroup
-//
-//	Class for placing groups of different objects
-//
-//	elements: Array of SimpleObjects
-//	avoidSelf: Objects will not overlap
-//	tileClass: Optional tile class to add with these objects
-//	x,z: Tile coordinates of center of placer
-//
-/////////////////////////////////////////////////////////////////////////////////////////
-
-function SimpleGroup(elements, avoidSelf, tileClass, x, z)
-{
-	this.elements = elements;
-	this.tileClass = tileClass !== undefined ? getTileClass(tileClass) : undefined;
-	this.avoidSelf = avoidSelf !== undefined ? avoidSelf : false;
-	this.x = x !== undefined ? x : -1;
-	this.z = z !== undefined ? z : -1;
-}
-
-SimpleGroup.prototype.place = function(player, constraint)
-{
-	var resultObjs = [];
-
-	// Try placement of objects
-	for (let element of this.elements)
-	{
-		var objs = element.place(this.x, this.z, player, this.avoidSelf, constraint);
-
-		if (objs === undefined)
-			return undefined;
-
-		resultObjs = resultObjs.concat(objs);
-	}
-
-	// Add placed objects to map
-	for (let obj of resultObjs)
-	{
-		if (g_Map.validT(obj.position.x / CELL_SIZE, obj.position.z / CELL_SIZE))
-			g_Map.addObject(obj);
-
-		// Convert position to integer number of tiles
-		if (this.tileClass !== undefined)
-			this.tileClass.add(Math.floor(obj.position.x/CELL_SIZE), Math.floor(obj.position.z/CELL_SIZE));
-	}
-
-	return resultObjs;
-};
-
-/////////////////////////////////////////////////////////////////////////////////////////
-//	RandomGroup
-//
-//	Class for placing group of a random simple object
-//
-//	elements: Array of SimpleObjects
-//	avoidSelf: Objects will not overlap
-//	tileClass: Optional tile class to add with these objects
-//	x,z: Tile coordinates of center of placer
-//
-/////////////////////////////////////////////////////////////////////////////////////////
-
-function RandomGroup(elements, avoidSelf, tileClass, x, z)
-{
-	this.elements = elements;
-	this.tileClass = tileClass !== undefined ? getTileClass(tileClass) : undefined;
-	this.avoidSelf = avoidSelf !== undefined ? avoidSelf : false;
-	this.x = x !== undefined ? x : -1;
-	this.z = z !== undefined ? z : -1;
-}
-
-RandomGroup.prototype.place = function(player, constraint)
-{
-	var resultObjs = pickRandom(this.elements).place(this.x, this.z, player, this.avoidSelf, constraint);
-	if (resultObjs === undefined)
-		return undefined;
-
-	// Add placed objects to map
-	for (let obj of resultObjs)
-	{
-		g_Map.addObject(obj);
-
-		// Convert position to integer number of tiles
-		if (this.tileClass !== undefined)
-			this.tileClass.add(Math.floor(obj.position.x/CELL_SIZE), Math.floor(obj.position.z/CELL_SIZE));
-	}
-
-	return resultObjs;
-};