Vrack 3

Vrack 3 is a single-level PWAD for Doom II designed by Fredrik Johansson. It was released in November 2003 and is the sequel to Vrack and Vrack 2. Vrack 3 includes an untitled custom music track.

Essentials
Like its predecessors, Vrack 3 is a massive map, and a combination of a consistent texture theme across the entire level, high inter-connectivity and need for backtracking at some points can translate to making finding out where to go extremely tricky. All this is on top of the map's impressive complement of monsters and liberal use of monster teleportation, including a massive teleport trap at the end of the level with a grand total of 119 monsters on Ultra-Violence and above - of which more than half on the monsters are revenants or more durable monsters!

Overview

Vrack 3 requires you to collect, in order, the yellow key, the red key and then the blue key before exiting via a spaceship docked in the northwest of the map. The areas involving collecting the yellow key are concentrated in the southern parts of the map; the areas involving collecting the red key are concentrated in the east and southeast of the map; the blue key sequence is confined to the extreme northeast of the map.

Southern Nexus - Yellow Key Sequence

Your objective in this part of the map is to collect the yellow key, hidden in the central pillar of the "southern nexus", a room with four bridges directly north of the starting room, then access the yellow door in the north of the "southern nexus". To do that, you will need to complete these sub-tasks:


 * Switch the bridges with the switch in the southeast of the "southern nexus"
 * Make your way into the Storage Area in the West
 * Open up the central pillar with the switch in the northeast of the "southern nexus" and collect the key
 * Using the switch in the northwest control room, switch the bridges to "North-South raised" and get to the yellow door in the north

Start - Switching the Bridges

You begin in a small hangar marked "Bay 9". Flip the switches on either side of the first door to raise it completely, then do the same with the switches on either side of the second door. You will be in the south of a large room with a central raised area, filled with the usual cannon fodder in all places. For brevity, this room will be termed the "southern nexus". This room has four bridges, one in each cardinal direction; when you start, the bridges running east-west will be raised and the bridges running north-south will be lowered. Grab the shotgun and box of shells, then the armor from the platform in the west, which will lower you to the floor of the southern nexus. On the floor, there a couple of barrels scattered everywhere. Since ammo is somewhat tight for this first stretch, use the barrel explosions to clear out enemies and save your shells. For example, in this first encounter, you can use the barrel in the southeast to clear out enemies on the floor.

Head through the door in the southeast of this area. This leads to a small corridor with a demon and a barrel. Again, blow up the barrel and continue forward. This leads into a large U-shaped area marked "Bay 3". Watch for shotgun guys, imps and demons on the floor, as well as shotgun guys and imps firing from windows in the north. Go through the door in the southwest of this area. This leads to a corridor with a "laser" warning on the wall and a cacodemon sealed in a nearby room behind four lasers. These lasers are instant death if you walk into them. Again, use the barrels behind the cacodemon to finish it off. At the top, open the door and you will find yourself in the blocked-off southeast part of the walkway in the southern nexus. Flip the switch here to lower the bridges going east-west and raise the bridges running north-south.

Accessing the Storage Area

Backtrack to the southern nexus. With the east-west bridges lowered, you can proceed to the northeast quadrant of the southern nexus' floor. As you do so, a small teleport trap activates (not on Hey, not too rough and below), causing one demon to appear behind you, one demon to appear from behind the door leading to Bay 3 in the east, and a Hell knight to appear in front of you. Again, use the barrels to set up an ammo-effective way of taking down these monsters.

In the north of the northeast quadrant, you will find a switch. Flip this switch to lower the north-south bridges and raise the east-west bridges, allowing access to the northwest quadrant of the floor. Three zombiemen and up to two revenants will attack. Once again, the barrels are your friends.

In the northwest quadrant, you will find a niche with a silver platform in the north. Lower it and ride it up to a short corridor with a sign marked "storage". Further up, you will find a square room with a crate being lifted up and down by a machine. Kill the two shotgun guys in here, then flip the switch in the northwest of the room to open up the silver wall in the west, revealing the Storage Area. carefully snipe out the cannon fodder scattered around the room (including up to three demons on the floor) before you drop down into the Storage Area.

Opposition in the Storage Area is fairly sparse, but if you pick up the chaingun in the south of the area, up to two cacodemons are released. Five chaingunners and two Hell knights will also teleport into the room at two spots, one in the north and one in the southwest. Three barrels are lined up near the teleport spot in the north, so detonate them at a good time for maximum effectiveness.

Head to the southwest of the Storage Area. Go up the steps, take a right turn (watch for chaingunners in the window ahead) and then another right turn to enter the overlook in the west of the Storage Area. Flip the switch on the north wall to raise steps in the east, allowing access to the raised corridor in the east of the Storage Area.

Revealing the Yellow Key

Head up the steps in the east of the Storage Area and follow the raised corridor around to its end. You will be in the west of the southern nexus. Run across the raised east-west bridges to a small silver door in the northeast of the southern nexus. Head through the small connecting corridor and you will find yourself in the raised area north of Bay 3. Make your way to the top and flip the switch at the overlook to open the central pillar in the southern nexus and reveal the yellow key.

Backtrack down to the door in the northeast of the southern nexus. Run across the bridge to the central pillar to collect the yellow key.

Switching the Bridges to access the Yellow Door

From the eastern bridge, drop to the southeast quadrant of the floor of the southern nexus. You need to go back to the Storage Area, so you need to perform the steps in Switching the Bridges again. However, when you reach the southeast part of the southern nexus walkway again, you will find that another alcove has opened with a switch in it, flanked by yellow bars. Kill the three shotgun guys inside, then flip both this new switch (opens a new room in the west) and the switch next to it (switches the bridges to "north-south raised").

Backtrack into the southern nexus, then repeat the steps to access the Storage Area (switch bridges with switch in the northeast quadrant, ride the platform in the northwest quadrant up, go around the corridor and jump out the open window). Watch for a newly released set of five lost souls and a pain elemental (Ultra-Violence and above only). Go back up the steps to the raised corridor in the east of the Storage Area. At the end of the corridor, you will find that a wall has opened in the north. This leads to the northwestern overlook in the southern nexus. Head in there and flip the switch to switch the bridges to "north-south raised" again.

Head back out and drop down to the southwest quadrant of the floor of the southern nexus. Ride the platform up, then run across the raised north-south bridge to the yellow door in the north.

Main Hangar and Red Key

To get to the red key, you must first get to the Main Hangar, open it up and survive your first large-scale outdoor battle of the level. This is where the progression of the level becomes rather tricky. To do that, you will need to complete these sub-tasks:


 * Flip the switch in the Inner North Areas
 * Use the conveyor belt in the Storage Area to access the Outer North Areas and the Main Hangar
 * Open the blast doors of the Main Hangar to access the Eastern Outdoor Area
 * Flip the switch in the southwest of the Eastern Outdoor Area and survive the battle
 * Collect the red key

Inner North Areas

When you open the yellow door in the north of the southern nexus, you will be immediately greeted by a baron of Hell. Shoot it down and continue forward to a 5-way junction with three lights. We will call the following sequence of rooms the "Inner North Area", and the 5-way junction with three lights "Inner North Junction". Through the numerous windows in the area, you will be able to see another big part of the level in the north, but there seems to be no way to access that area yet from any of the rooms in this current sequence - we will call that part of the level "Outer North Areas".

The first thing that you will realise is that the Inner and Outer North Areas are quiet - too quiet. There are no enemies in the area at all. From Inner North Junction, head west, then south. You will come to a room with three large spots of light on the floor and a super shotgun on a pedestal. Grab the super shotgun, and three thing happen:


 * Bars lower, blocking the doors for about 30 seconds.
 * A trap in the east opens, with two (three on Ultra-Violence and above) mancubi. One of them will immediately teleport to the west of the room.
 * A teleport trap activates and the Inner North Areas begin to fill with a large number of shotgun guys and imps, particularly to the north, east and west of Inner North Junction.

Go through the door in the west. The Outer North Areas will begin to populate with a wide variety of monsters, so you might wish to stay clear of the window in the north unless you wish to take them out immediately. Instead of heading down the steps in this room, go around to the south side of the room and flip the switch on the west wall. Next, open the door in the east to find yourself in a raised alcove in the west of the Storage Area. Jump out from here to be back in the Storage Area.

Conveyor Belt, Outer North Areas and Main Hangar

Head to the southeast of the Storage Area. A room with an armor is now open. Head into this room and flip the switch. This causes a pillar in the conveyor belt to the north to raise up. Leave this room and head to the conveyor belt north of it. Run north along it to a small area with some crates. Blow up the barrel in the west to kill the shotgun guy and imp in the west, then jump off to the west side and continue north to access the Outer North Areas.

In here, you probably will have a lot of house-cleaning to do, considering that you have a large number of mid-strength monsters in the form of chaingunners, revenants and Hell knights to slaughter. Clean up, head east and up the stairs (you can flip the switch in the room west of the stairs to grab a collect a berserk pack in the pit in the west of this area), then follow the passageway round to a vaguely octagonal room with up to three revenants and four lost souls. Exit this room through the door in the east, and you will arrive at the Main Hangar. Mop up the zombiemen in here. You can take the rocket launcher now or later, but collect the boxes of rockets before you collect it. Once you collect the rocket launcher, up to 12 mancubi will teleport to all four sides of this room. Since a soulsphere is available later, you might want to grab the rocket launcher later when you have more health.

Red Key Sequence - Opening Main Hangar, Eastern Outdoor Area, Red Key Chamber

In the Main Hangar, go up the steps in the southwest and open the unlocked door in the southwest. In this next corridor, watch for shotgun guys and a baron of Hell. Take the path heading west to come to a small room southeast of the Inner North Junction. Flip the switch on the west wall, then go through the door (this is a one way door). This switch raised steps to the door in the east of the Inner North Junction. Head up these steps to the overlook in the west of the Main Hangar. Flip the switch to open the blast doors.

From the Inner North Junction, head west. Notice that a door has opened in the north wall of the overlook west of the Inner North Junction. Head through this door and head down the steps to the Outer North Areas. You can now grab the soulsphere from the pit in the west. Collect it, then backtrack to the Main Hangar.

Back in the Main Hangar, if you have not collected the rocket launcher and completed the mancubus battle yet, do so now. Once done, jump out of the Main Hangar through the open blast door, or by riding any of the two platforms in the northeast of southeast (each with a box of shells) down. You will arrive on the L-shaped upper ledge of the Eastern Outdoor Area. As you turn the corner in the southwest of this area, up to nine arachnotrons will teleport in - four in the northwest, five in the southeast. The platforms back to the Main Hangar will also become blocked. You will find yourself in a crossfire of plasma with almost zero cover. Equip your rocket launcher, check your standoff distance and hold down the fire button for dear life. Ideally, you should clear the arachnotrons in the northwest first, then those in the southeast, because the switch in the southeast is protected by another teleport trap.

Once all the arachnotrons are dead, head for the switch in the southeast and flip it. This will raise steps in the northwest, allowing access to the red key chamber. However, it also triggers a large teleport trap. Large numbers of imps and revenants will teleport to areas on and around the Eastern Outdoor Area. Cacodemons are also released from the northeast. You must pay attention to revenants behind the bars in the southeast, those looking out from the Main Hangar's opening and on the platform in the northwest, as their homing rockets can quickly decimate your health.

Once the coast is clear, head up the steps in the northwest to a 4-way junction. To the south is a red door, to the west is the red key chamber and to the north is a locked door. Pay attention to the last door - knowing that it is a monster closet will be life-saving later.

Head into the red key chamber and flip the switch in the southwest. This lowers the red key pedestal, but also releases two Hell knights (Hurt me plenty and below) or three barons of Hell (Ultra-Violence and above). When you backtrack into the junction, you will find that the locked door in the north has also opened, revealing a Hell knight (Hurt me plenty and below) or a baron of Hell (Ultra-Violence and above). While all this is happening, the Main Hangar is being populated with a horde of strong enemies, including one arch-vile that appears at the overlook in the west of the Main Hangar. You are suggested to take out the Hell nobles first, then the arch-vile (with rockets). After that, head back into the Main Hangar through the red door and mop up.

Laser Maze

To get to the northeast part of the level where the blue key is, you will have to unblock the bars leading to the lower ledge in the Eastern Outdoor Area. Unfortunately, that is far easier said than done - getting there involves going through the Laser Maze, one of the nastiest parts of the level. With teleporting cacodemons and a climatic encounter that is extremely difficult to survive (unless you use a secret area), you are in for one rough ride here. Your objectives are as follows:


 * Activate the north switch unlocking the Laser Maze
 * Activate the south switch unlocking the Laser Maze
 * Enter the Laser Maze and get to the switch
 * Escape the Laser Maze

Laser Maze Access - Southern Switch

From the Main Hangar, go through the red door in the southeast. Collect the backpack from the broken crate, then flip the switch at the end of the corridor. The inner wall of the corridor will lower, revealing the rest of the room. There are initially up to two mancubi in here, and two more will teleport in near the door shortly after. Deal with them and flip the switch on the pedestal to open one of the two doors blocking access to the Laser Maze.

Laser Maze Access - Northern Switch

From the Main Hangar, go up the steps in the southeast and open the unlocked door. Head all the way down the corridor and open the red door. You will be back in the area after the door in the northeast of the southern nexus. Backtrack all the way down to the short connecting corridor, and you will find that a new stairway has appeared in the south, connecting this short corridor to the corridor leading to Bay 3. Head down the staircase, go to Bay 3 and open the red door in the east (watch for a pack of revenants). In this room, flip the switch on the pedestal to open one of the two doors blocking access to the Laser Maze.

Surviving the Laser Maze

Head back into the corridor linking the southern nexus to Bay 3, then take the steps up and go east to return to the area north of Bay 3. Find the corridor in the east wall and go through it to a red door. Open this red door and continue along the walkway to a flight of steps leading to a hole. Drop into this hole to enter the Laser Maze.

The Laser Maze is designed around a 5x6 grid, and is in essence a massive switch hunt. Some walls are lasers that will kill you instantly, others raise and lower via tripwires and switches. The bigger problem are the teleporting cacodemons. This area has many invisible monster-only teleport lines, and they have been deviously positioned and directed to maximise the possibility that a cacodemon will teleport into (or near) the cell you are standing in. The maze contains up to 23 cacodemons, if you are counting kills. Labelling the columns from 1-6 and the rows from A to E, these are the cells you need to go to and the switches that you need to press:


 * 1) C2 East Wall
 * 2) D2 East Wall
 * 3) B2 East Wall
 * 4) B4 North Wall
 * 5) B2 North Wall
 * 6) C2 West Wall
 * 7) B6 West Wall

This allows you access the switch room north of A3. Flip this switch to lower it, and collect a megasphere which you will need. Up to ten revenants and two arch-viles will be released from a trap south of cell E3 - and they get to benefit from the teleporting as well. Dump everything you have on these monsters, because this is going to be one mad climatic fight. Before you can leave this area, there's a couple more things you need to do, so bear these in mind while attempting to wipe out the enemies:


 * Flip switch at D6.
 * Go to C4 and cross into D4. Walls will lower, revealing a hidden room south of E4. Flip the switch in this room.
 * Make your way to A1 and exit the Laser Maze.

Gate Lab - Blue Key Sequence and Finale

The last part of the level is composed of three parts: A cyberdemon battle, an elevator puzzle and a final battle best described as "the mother of all teleport traps". Your objectives in this part are:


 * Access the Gate Lab
 * Solve the elevator puzzle and get the blue key and a BFG9000
 * Initiate the final battle, survive and exit

Access the Gate Lab

After the Laser Maze, you will emerge in the Eastern Outdoor Area again. In the southwest, you will find that a set of bars blocking a set of steps heading down into a lower ledge have been unblocked. Head down these steps and proceed north to the large blast door in the northeast of the Eastern Outdoor Area. Open it and you will find a large hangar with a cyberdemon, as well as numerous boxes of rockets. This area is not amenable to circlestrafing, so you are just going to have to use positioning and micro-dodging to your advantage, bullet hell game style.

Once the cyberdemon has been vanquished, open the door in the west of the large hangar. Follow this corridor to its end and open the door. Kill the two demons ahead, then go through the teleporter to end up on the other side of the area, where you will find two more demons and two zombiemen. Continue down the corridor to a large hall filled with zombiemen. Drop into the pit in the northeast of this area to end up in the Gate Lab proper, where you have to solve the elevator puzzle.

Gate Lab: Elevator Puzzle (Optimal Solution)

Clear the room of enemies first before handling the puzzle. The Gate Lab puzzle uses six elevators and six pairs of control switches. Three of them are in the northern half of the room and three of them are in the southern half of the room. The halves are divided by a laser beam array, butt here are side passages that allow crossing over.Your goal is to raise all six elevators in a manner that allows you to collect the BFG9000 in the southern half and the blue key in the northern half. For brevity, the elevator will be named as N, NE, NW and S, SE, SW based on their rough position in the room.

First, you need to figure out which switch controls which elevator. In order:


 * North side, from west to east: S, NW, N
 * South side, from west to east: NE, SW, SE.

Next, we need to consider the state of the elevators. The starting state is SW LOW, NW HIGH, N LOW; NE HIGH SE LOW S HIGH.

Our first goal is to cross over to the north side after setting as many elevators to HIGH as possible. The "high route" to the BFG9000 on the east side of the room is almost complete except for elevator SE, which needs to be set to HIGH. Thus, we switch elevator SE to HIGH using the eastern switch in the south. Next, we need to set elevators SW and N to HIGH, but elevator N can only be controlled from the north side. However, with elevators SW and SE set at HIGH and elevator N at LOW, we can cross over to the north side using the "high route" in the west (although the blue key will be blocked off). Thus, we set elevator SW to HIGH using the middle switch in the south. This allows us to use the southwest staircase to cross over to the north side. On the north side, all we need to do is use the eastern switch to set elevator N to HIGH, making all six platforms set at HIGH. This allowing us to use the northeast staircase to collect the BFG and drop off into the southern side, then use the southwest staircase to collect the blue key.

Thus, in a nutshell:


 * Flip the "up" switches in the center and eastern switch banks on the south side.
 * Use the southwest staircase to cross over to the northern side.
 * Flip the "up" switch in the eastern switch bank on the north side.
 * Run up the northeast staircase and along the high path to the BFG9000.
 * Drop down to the south side and run up the southwest staircase. Follow the high path to the blue key.

Collecting the blue key triggers the room to fill with more tough monsters, including an arch-vile that is likely to use the blue door in the south to enter and wreck havoc. Use your new-found BFG9000 to wipe them out, but don't get too liberal on your use of cells here - you will need them for the upcoming final battle.

Exit the Gate Lab through the blue door in the south.

Finale

Flip the switch in the east to raise the bars and get back on the eastern ledge with a teleporter. Step through the teleporter to be teleported to the west side of this area and return to the large hall before you dropped down into the Gate Lab. Head up the steps in the west, through another big hall, then through either blue door. You might want to quick-save here, because only one massive encounter stands between you and completing this level. In this large final outdoor area, all is quiet. You can see your spaceship moored in the northwest, but the path to it is blocked by bars. Head to the southwest of the walkway to find a small maintenance bay with a switch panel. Collect the ammo, pull out your BFG9000, take a deep breath and flip the switch.

A grand total of 117 tough monsters (on Ultra-Violence) are going to swamp the outdoor walkway, the hall east of the blue doors and even the areas to the south overlooking this final area. Put BFG shots and rockets downrange to clear the path back towards the blue doors, and detour for medikits if necessary. In the northeast of the hall east of the blue doors, a new passageway will have opened. Continue unloading BFG rounds to clear this room out, then flip the switch in this room to lower the bars blocking the path to the spaceship.

Now, you'll have to fight your way back down with the last of your BFG9000 ammo. Clear a path to the west and make a dash across the bridge to the platform the spaceship is moored on. Clear out or go around the Hell nobles here to the spaceship's staircase, and press use on the door of the spaceship to mark an end to this massive, impressive and difficult level.

Secrets

 * 1) In the first big room with four bridges, after running east across the east-west bridges, approach the small metal door in the northeast. This causes the stack of crates in the northeast to temporarily lower. Ride it up to a metal recess in the wall. Open the metal recess to reveal an alcove with a megaarmor (sector 604)
 * 2) After flipping the switch high in the northeast of the first big room with four bridges, the yellow key is revealed in the center of this room. Return to the starting room to find that the west wall has opened, revealing a box of ammo and a backpack. (sector 2839)
 * 3) After collecting the red key, head back into the main hangar in the east of the level and go through the northwest red door. This leads to a room with a plasma gun and four energy cells. On the south wall, to the right of the inset with computer panels and to the left of the window, you will find a region of wall between two pillars that is divided by two pairs of metal stripes, one of which seems out of place. Press on the section of this wall that is between the two pairs of metal stripes, and it will open revealing a teleporter. Step into this teleporter to be teleported on top of a pile of crates in the southeast of the level. (sector 1324)
 * 4) In the laser beam maze, get to the easternmost cell in the second row from the north (it has a stack of two big crates beside a small crate). Open the north wall of this cell to reveal a hidden alcove with an invulnerability, which will be vital in the area's major encounter. (sector 2593)

Current records
The records for the map at the Doomed Speed Demos Archive are:

Things
This level contains the following numbers of things per skill level:

Technical information
Instant-death lasers using voodoo doll telefrag

In a number of areas in the level, there are arrays of four parallel lasers that will instantly kill the player if he steps through them. This is achieved through teleport lines on either side of the laser that teleport the player on top of a voodoo doll, causing the player to telefrag himself. However, this map utilises Boom's silent teleporters, which have no fog flash and preserve angle and momentum, to improve on previous implementations of such a system (such as those seen in ) and make it seem like the player has simply been instantly killed by walking through the laser.

Multi-action switches using voodoo dolls and carrying sectors

In the first big room with four bridges, a number of the switches around the room are capable of lowering one set of bridges and raising the other in rapid succession. This is achieved using a voodoo doll and conveyor belt system. In a control sector off the map, a voodoo doll is placed in a narrow rectangular sector sharing a tag with a linedef with type 253 (Scroll floor, move things). This scrolls the voodoo doll along the sector. However, under normal circumstances, a small lowered segment of ceiling prevents the voodoo doll from proceeding any further along the sector.

The action of these switches is merely to raise this lowered segment of ceiling in the control sector. This allows the voodoo doll to be scrolled further forward along the sector. It then crosses the following lines in order:


 * Raise one pair of bridges
 * Re-lower the segment of ceiling in the control sector
 * Lower the other pair of bridges
 * Teleport the voodoo doll back to the other end of the control sector, where it will scroll forward and be stopped by the lowered segment of ceiling again.

Since the four bridges have only two states, there is a pair of control sectors (sectors 12 and 15) with corresponding lowered segments of ceilings (sectors 13 and 16). All switches changing the state of the bridges to "east-west raised" merely raise the ceiling of sector 16; all switches changing the state of the bridges to "north-south raised" merely raise the ceiling of sector 13.