diff --git a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/RegularLevel.java b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/RegularLevel.java
index 29180eaf8..1cab100a6 100644
--- a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/RegularLevel.java
+++ b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/RegularLevel.java
@@ -46,15 +46,12 @@ import com.watabou.utils.Rect;
 
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.HashSet;
 import java.util.Iterator;
-import java.util.LinkedList;
 import java.util.List;
 
 public abstract class RegularLevel extends Level {
 
-	protected HashSet<Room> rooms;
+	protected ArrayList<Room> rooms;
 	
 	protected Room roomEntrance;
 	protected Room roomExit;
@@ -94,7 +91,7 @@ public abstract class RegularLevel extends Level {
 		roomEntrance.type = Type.ENTRANCE;
 		roomExit.type = Type.EXIT;
 		
-		HashSet<Room> connected = new HashSet<Room>();
+		ArrayList<Room> connected = new ArrayList<>();
 		connected.add( roomEntrance );
 
 		Graph.buildDistanceMap( rooms, roomExit );
@@ -183,7 +180,7 @@ public abstract class RegularLevel extends Level {
 	
 	protected boolean initRooms() {
 
-		rooms = new HashSet<>();
+		rooms = new ArrayList<>();
 		split( new Rect( 0, 0, width() - 1, height() - 1 ) );
 		
 		if (rooms.size() < 8) {
@@ -251,7 +248,7 @@ public abstract class RegularLevel extends Level {
 					
 				} else if (Random.Int( 2 ) == 0){
 
-					HashSet<Room> neigbours = new HashSet<Room>();
+					ArrayList<Room> neigbours = new ArrayList<>();
 					for (Room n : r.neigbours) {
 						if (!r.connected.containsKey( n ) &&
 							!Room.SPECIALS.contains( n.type ) &&
@@ -341,7 +338,7 @@ public abstract class RegularLevel extends Level {
 		float[] trapChances = trapChances();
 		Class<?>[] trapClasses = trapClasses();
 
-		LinkedList<Integer> validCells = new LinkedList<Integer>();
+		ArrayList<Integer> validCells = new ArrayList<>();
 
 		for (int i = 0; i < length(); i ++) {
 			if (map[i] == Terrain.EMPTY){
@@ -360,11 +357,10 @@ public abstract class RegularLevel extends Level {
 		//no more than one trap every 5 valid tiles.
 		nTraps = Math.min(nTraps, validCells.size()/5);
 
-		Collections.shuffle(validCells);
-
 		for (int i = 0; i < nTraps; i++) {
 			
-			int trapPos = validCells.removeFirst();
+			Integer trapPos = Random.element(validCells);
+			validCells.remove(trapPos); //removes the integer object, not at the index
 
 			try {
 				Trap trap = ((Trap)trapClasses[Random.chances( trapChances )].newInstance()).hide();
@@ -584,7 +580,7 @@ public abstract class RegularLevel extends Level {
 		//on floor 1, 10 rats are created so the player can get level 2.
 		int mobsToSpawn = Dungeon.depth == 1 ? 10 : nMobs();
 
-		HashSet<Room> stdRooms = new HashSet<>();
+		ArrayList<Room> stdRooms = new ArrayList<>();
 		for (Room room : rooms) {
 			if (room.type == Type.STANDARD) stdRooms.add(room);
 		}
@@ -764,7 +760,7 @@ public abstract class RegularLevel extends Level {
 	public void restoreFromBundle( Bundle bundle ) {
 		super.restoreFromBundle( bundle );
 
-		rooms = new HashSet<>( (Collection<Room>) ((Collection<?>) bundle.getCollection( "rooms" )) );
+		rooms = new ArrayList<>( (Collection<Room>) ((Collection<?>) bundle.getCollection( "rooms" )) );
 		for (Room r : rooms) {
 			if (r.type == Type.WEAK_FLOOR) {
 				weakFloorCreated = true;
diff --git a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/Room.java b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/Room.java
index 42a21d85c..6867ed0ed 100644
--- a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/Room.java
+++ b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/Room.java
@@ -61,13 +61,12 @@ import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.HashMap;
-import java.util.HashSet;
+import java.util.LinkedHashMap;
 
 public class Room extends Rect implements Graph.Node, Bundlable {
 	
-	public HashSet<Room> neigbours = new HashSet<Room>();
-	public HashMap<Room, Door> connected = new HashMap<Room, Door>();
+	public ArrayList<Room> neigbours = new ArrayList<Room>();
+	public LinkedHashMap<Room, Door> connected = new LinkedHashMap<Room, Door>();
 	
 	public int distance;
 	public int price = 1;
@@ -126,8 +125,13 @@ public class Room extends Rect implements Graph.Node, Bundlable {
 			}
 		}
 	};
+
+	private static final ArrayList<Type> ALL_SPEC = new ArrayList<Type>( Arrays.asList(
+		Type.WEAK_FLOOR, Type.MAGIC_WELL, Type.CRYPT, Type.POOL, Type.GARDEN, Type.LIBRARY, Type.ARMORY,
+		Type.TREASURY, Type.TRAPS, Type.STORAGE, Type.STATUE, Type.LABORATORY, Type.VAULT
+	) );
 	
-	public static final ArrayList<Type> SPECIALS = new ArrayList<Type>( Arrays.asList(
+	public static ArrayList<Type> SPECIALS = new ArrayList<Type>( Arrays.asList(
 		Type.WEAK_FLOOR, Type.MAGIC_WELL, Type.CRYPT, Type.POOL, Type.GARDEN, Type.LIBRARY, Type.ARMORY,
 		Type.TREASURY, Type.TRAPS, Type.STORAGE, Type.STATUE, Type.LABORATORY, Type.VAULT
 	) );
@@ -221,6 +225,7 @@ public class Room extends Rect implements Graph.Node, Bundlable {
 	}
 	
 	public static void shuffleTypes() {
+		SPECIALS = (ArrayList<Type>)ALL_SPEC.clone();
 		int size = SPECIALS.size();
 		for (int i=0; i < size - 1; i++) {
 			int j = Random.Int( i, size );