diff --git a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/SewerBossLevel.java b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/SewerBossLevel.java
index 7f3f9b44c..146340610 100644
--- a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/SewerBossLevel.java
+++ b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/SewerBossLevel.java
@@ -29,8 +29,10 @@ import com.shatteredpixel.shatteredpixeldungeon.actors.mobs.Mob;
 import com.shatteredpixel.shatteredpixeldungeon.items.Heap;
 import com.shatteredpixel.shatteredpixeldungeon.items.Item;
 import com.shatteredpixel.shatteredpixeldungeon.levels.builders.Builder;
+import com.shatteredpixel.shatteredpixeldungeon.levels.builders.LoopBuilder;
 import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.Room;
 import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.special.RatKingRoom;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.EmptyRoom;
 import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.SewerBossEntranceRoom;
 import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.StandardRoom;
 import com.shatteredpixel.shatteredpixeldungeon.scenes.GameScene;
@@ -55,7 +57,7 @@ public class SewerBossLevel extends SewerLevel {
 		
 		int standards = standardRooms();
 		for (int i = 0; i < standards; i++)
-			initRooms.add(StandardRoom.createRoom());
+			initRooms.add(new EmptyRoom());
 		
 		initRooms.add(new RatKingRoom());
 		return initRooms;
@@ -67,16 +69,18 @@ public class SewerBossLevel extends SewerLevel {
 	}
 	
 	protected Builder builder(){
-		//TODO want to use a more simple circular builder here
-		return super.builder();
+		return new LoopBuilder()
+				.setPathLength(1f, new float[]{1})
+				.setTunnelLength(new float[]{2, 3}, new float[]{1});
 	}
 	
 	@Override
 	protected void placeSign() {
 		while (true) {
-			int pos = pointToCell(roomEntrance.random());
+			int pos = pointToCell(roomEntrance.random(2));
 			if (map[pos] != Terrain.LOCKED_EXIT
-					&& map[pos] != Terrain.WALL_DECO) {
+					&& map[pos] != Terrain.WALL_DECO
+					&& map[pos] != Terrain.ENTRANCE) {
 				map[pos] = Terrain.SIGN;
 				break;
 			}
@@ -112,8 +116,8 @@ public class SewerBossLevel extends SewerLevel {
 		Mob mob = Bestiary.mob( Dungeon.depth );
 		Room room;
 		do {
-			room = Random.element(rooms);
-		} while (!(room instanceof StandardRoom) || room == roomEntrance);
+			room = randomRoom(StandardRoom.class);
+		} while (room == roomEntrance);
 		mob.pos = pointToCell(room.random());
 		mobs.add( mob );
 	}
@@ -129,14 +133,18 @@ public class SewerBossLevel extends SewerLevel {
 			int pos;
 			do {
 				pos = pointToCell(roomEntrance.random());
-			} while (pos == entrance || map[pos] == Terrain.SIGN);
+			} while (pos == entrance || map[pos] == Terrain.SIGN || solid[pos]);
 			drop( item, pos ).type = Heap.Type.REMAINS;
 		}
 	}
 
 	@Override
 	public int randomRespawnCell() {
-		return pointToCell(roomEntrance.random());
+		int pos;
+		do {
+			pos = pointToCell(roomEntrance.random());
+		} while (pos == entrance || map[pos] == Terrain.SIGN || solid[pos]);
+		return pos;
 	}
 
 	
diff --git a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/builders/LoopBuilder.java b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/builders/LoopBuilder.java
new file mode 100644
index 000000000..563e6803d
--- /dev/null
+++ b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/builders/LoopBuilder.java
@@ -0,0 +1,228 @@
+/*
+ * Pixel Dungeon
+ * Copyright (C) 2012-2015  Oleg Dolya
+ *
+ * Shattered Pixel Dungeon
+ * Copyright (C) 2014-2017 Evan Debenham
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package com.shatteredpixel.shatteredpixeldungeon.levels.builders;
+
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.Room;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.special.ShopRoom;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.EntranceRoom;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.ExitRoom;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.standard.StandardRoom;
+import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.tunnel.TunnelRoom;
+import com.watabou.utils.Random;
+
+import java.util.ArrayList;
+
+//A builder with one core loop as its primary element
+public class LoopBuilder extends Builder {
+	
+	//TODO customizeable equation for angle changes (currently we're just linear)
+	
+	//path length is the percentage of pathable rooms that are on the loop
+	private float pathLength = 0.1f;
+	//The chance weights for extra rooms to be added to the path
+	private float[] pathLenJitterChances = new float[]{0, 2, 1};
+	
+	public LoopBuilder setPathLength( float len, float[] jitter ){
+		pathLength = len;
+		pathLenJitterChances = jitter;
+		return this;
+	}
+	
+	private float[] pathTunnelChances = new float[]{2, 3, 1};
+	private float[] branchTunnelChances = new float[]{3, 2, 1};
+	
+	public LoopBuilder setTunnelLength( float[] path, float[] branch){
+		pathTunnelChances = path;
+		branchTunnelChances = branch;
+		return this;
+	}
+	
+	private float extraConnectionChance = 0.1f;
+	
+	public LoopBuilder setExtraConnectionChance( float chance ){
+		extraConnectionChance = chance;
+		return this;
+	}
+	
+	@Override
+	public ArrayList<Room> build(ArrayList<Room> rooms) {
+		
+		Room entrance = null;
+		Room exit = null;
+		Room shop = null;
+		
+		ArrayList<Room> multiConnections = new ArrayList<>();
+		ArrayList<Room> singleConnections = new ArrayList<>();
+		
+		for (Room r : rooms){
+			if (r instanceof EntranceRoom){
+				entrance = r;
+			} else if (r instanceof ExitRoom) {
+				exit = r;
+			} else if (r instanceof ShopRoom && r.maxConnections(Room.ALL) == 1){
+				shop = r;
+			} else if (r.maxConnections(Room.ALL) > 1){
+				multiConnections.add(r);
+			} else if (r.maxConnections(Room.ALL) == 1){
+				singleConnections.add(r);
+			}
+		}
+		
+		if (entrance == null){
+			return null;
+		}
+		
+		entrance.setSize();
+		entrance.setPos(0, 0);
+		
+		float startAngle = Random.Float(0, 360);
+		
+		ArrayList<Room> loop = new ArrayList<>();
+		int roomsOnLoop = (int)(multiConnections.size()*pathLength) + Random.chances(pathLenJitterChances);
+		roomsOnLoop = Math.min(roomsOnLoop, multiConnections.size());
+		if (exit != null) roomsOnLoop++;
+		roomsOnLoop++;
+		
+		for (int i = 0; i < roomsOnLoop; i++){
+			if (i == 0)
+				loop.add(entrance);
+			else if (exit != null && i == roomsOnLoop/2)
+				loop.add(exit);
+			else
+				loop.add(multiConnections.remove(0));
+			
+			int tunnels = Random.chances(pathTunnelChances);
+			for (int j = 0; j < tunnels; j++){
+				loop.add(new TunnelRoom());
+			}
+		}
+		
+		Room prev = entrance;
+		float targetAngle = startAngle;
+		float angleChange = 360f / loop.size();
+		for (int i = 0; i < loop.size(); i++){
+			Room r = loop.get(i);
+			targetAngle += angleChange;
+			float placeAngle;
+			if ((placeAngle = placeRoom(rooms, prev, r, targetAngle)) != -1) {
+				//targetAngle += (targetAngle - placeAngle);
+				prev = r;
+				if (!rooms.contains(prev))
+					rooms.add(prev);
+			}
+		}
+		
+		//FIXME this is lazy, there are ways to do this without relying on chance
+		if (!prev.connect(entrance)){
+			return null;
+		}
+		
+		ArrayList<Room> branchable = new ArrayList<>();
+		for (Room r : loop){
+			if (r instanceof StandardRoom) branchable.add(r);
+		}
+		
+		int i = 0;
+		
+		Room curr;
+		float angle;
+		int tries;
+		ArrayList<Room> tunnelsThisBranch = new ArrayList<>();
+		//TODO this is almost identical to logic in linebuilder, can probably generalize
+		while (i < multiConnections.size() + singleConnections.size()){
+			
+			tunnelsThisBranch.clear();
+			curr = Random.element(branchable);
+			
+			int tunnels = Random.chances(branchTunnelChances);
+			for (int j = 0; j < tunnels; j++){
+				TunnelRoom t = new TunnelRoom();
+				tries = 10;
+				
+				do {
+					angle = placeRoom(rooms, curr, t, Random.Float(360f));
+					tries--;
+				} while (angle == -1 && tries >= 0);
+				
+				if (angle == -1) {
+					for (Room r : tunnelsThisBranch){
+						r.clearConnections();
+						rooms.remove(r);
+					}
+					tunnelsThisBranch.clear();
+					break;
+				} else {
+					tunnelsThisBranch.add(t);
+					rooms.add(t);
+				}
+				
+				curr = t;
+			}
+			
+			if (tunnelsThisBranch.size() != tunnels){
+				continue;
+			}
+			
+			Room r;
+			if (i < multiConnections.size()) {
+				r = multiConnections.get(i);
+			} else {
+				r = singleConnections.get(i - multiConnections.size());
+			}
+			
+			tries = 10;
+			
+			do {
+				angle = placeRoom(rooms, curr, r, Random.Float(360f));
+				tries--;
+			} while (angle == -1 && tries >= 0);
+			
+			if (angle == -1){
+				for (Room t : tunnelsThisBranch){
+					t.clearConnections();
+					rooms.remove(t);
+				}
+				tunnelsThisBranch.clear();
+				continue;
+			}
+			
+			
+			if (r.maxConnections(Room.ALL) > 1 && Random.Int(2) == 0)
+				branchable.add(r);
+			
+			i++;
+		}
+		
+		findNeighbours(rooms);
+		
+		for (Room r : rooms){
+			for (Room n : r.neigbours){
+				if (!n.connected.containsKey(r)
+						&& Random.Float() < extraConnectionChance){
+					r.connect(n);
+				}
+			}
+		}
+		
+		return rooms;
+	}
+}
diff --git a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/rooms/Room.java b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/rooms/Room.java
index 0e4ce5720..416531dae 100644
--- a/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/rooms/Room.java
+++ b/core/src/main/java/com/shatteredpixel/shatteredpixeldungeon/levels/rooms/Room.java
@@ -250,6 +250,17 @@ public class Room extends Rect implements Graph.Node, Bundlable {
 		return false;
 	}
 	
+	public void clearConnections(){
+		for (Room r : neigbours){
+			r.neigbours.remove(this);
+		}
+		neigbours.clear();
+		for (Room r : connected.keySet()){
+			r.connected.remove(this);
+		}
+		connected.clear();
+	}
+	
 	// **** Graph.Node interface ****
 
 	@Override