The Ultimate DOOM/Walkthrough

Map 1: Hangar
This level is pretty easy, turn left and proceed to the first doorway, shoot the guards (if any - depends on difficulty setting) go up the stairs to the end (you can't fall through the windows). You should have the green armor now, go down the stairs and run around left and right sides to pick up the stuff there. On Game Boy Advance no columns, but on PC look for switch on columns and you can get outside if you run back the way you came. Otherwise proceed out the door to the left picking up armor points (helmets), as you continue left you'll come to a door. When you open it there will be guard(s) shooting at you from a transporter about 20 feet (6m) ahead. Shoot as you open the door and kill them, get the stuff from the transporter and continue to the left picking up the armor points. Around the back of the transporter you'll see a doorway to the left. There will be at least one guard there, shoot him. In front of you will be a large room with an Imp on a platform and guards(s). Stay to the right and shoot the Imp ducking to the right to avoid it's fire. After the Imp is dead kill the guards and at the end of the zig-zag walkway turn to the right wall in the hallway and push on it (open it) go down there and run over the center to get the blue armor. Pick up all the stuff you can and return to the hallway. Open the door at the end and shoot the Imp(s). Open the exit and then go back to where the Imp that was on the platform. You can run over to the now lowered platform and get the shotgun and other stuff. Then proceed through the exit, pick up stuff and hit the big red button. (Or flip the switch and save the game on Gameboy Advance A button to go to next level, then right, A, right A to save in first slot.)

Map 2: Nuclear Plant
Ok, you have guards to the left and right, most to the right. Go to the left wall and turn to the right and shoot the trashcans and guards. Then run ahead into the structure you see and turn left then right up the lift and get the stuff there. Getting back down try for the green armor across the way if you don't have it already (you should, in which case you can't get it). Kill all the guards around the center room, then look at the outer wall of that center room and you'll see a dark area (brown) by the light panel in the center. Push on the wall and enter. Pick up any stuff you need and flip the switch up. Exit this hidden room and go forward heading for either of the two doorways in the opposite wall without color markings around them. Open one - shoot the guard(s) [likely on stairs] and go up the stairs, shooting left and right at the top to kill the guards. If you see the door to outside go out and get the machine gun and other stuff out there (that's what the switch you flipped opens). You'll get a red key card at the top of the stairs there and some other stuff (blue ball is 200 health points, machine gun and boxes of ammo are out there as well), then back down (may have to kill another guard) and out to the Red Door (on other side of center room from where you are). Just inside you'll find a hall and have to shoot some guards. To your left will be a room with a pool of green goo and possibly imps with a column and little island in the middle. Go there collect the stuff on the island then flip the switch on the column and quickly head back out across the hallway to the new area you just opened. There will be plenty of guards, imps, traps and stuff. When you get finished there to back out the to the hallway and left down the hallway, up the stairs (shoot the guard). At the top there is a zig-zag corrior, right, left, left, right and there should be another hidden doorway near the start of the left wall. It will lead down to the next section, run down, shoot like crazy and go back up. If you fall off, just kill everything and then pick up the stuff. Otherwise continue on down the lift and shoot the imps and guards there (if any are left). Pick up all the stuff then flip the switch, it will open a door in the wall (to your left [gameboy] or right [PC] depending on the version), enter it. Go all the way down and open the exit door, shoot the guards. Enter and flip the switch on the column (in the center) [Save game on gameboy Advance].

Map 3: Toxic Refinery
Get the stuff in the room open the door, go left and down the hall, shoot the guard(s), continue to the end of the hall and open the door and shoot (kill imps and guards). After killing them, enter and go up the three steps and look along the wall to your left you'll find a doorway. Go down stairs, left kill the imp and any guards, then flip the switch there, then go across to the lift and up to get the stuff there. There will likely be a guard to kill. When you come down again there maybe an imp or guard waiting (if so shoot it). Otherwise proceed up the steps and shoot the guard in the hallway, open the door, shoot the other guards and continue. At the end to the right will be and open area and guards and imps shooting from the wall and the area on the other side. Shoot them and proceed to the other side, shooting the guards in that hallway (left and a turn to the right), collect the objects but save the blue key card to last. Stand in front of it, turn around and back into it then shoot a little to the left (imp in new room that opens). Get the stuff from there and go back the way you came all the way out, back to where you entered and then continue on to the hallway that was on the right of where you came in to this level. Shoot any guards and open the blue door and shoot the imps and guards then enter. Go slightly left and enter the doorway, then right down the hall, shooting guards that appear. At the end of the hall there are a lot of guards, some hidden. After killing them there is a doorway in the center and you have to start up it to get the stairs to rise (shooting). Shoot all the stuff in front of you as the stairs rise enter the big room at the top and get any stuff you can, then open the door get any more stuff you can and flip the switch (next level save game on gameboy advance).

Map 4: Command Control
Notice the grey on the left wall? Try to open it there. On the gameboy you won't notice this, but the area still opens and the same stuff is there. Things are more complicated now, your finally going to need all three key cards to complete this level and make it through quite a maze. Through the door in front of you is an open area mostly to your left, three doorways in the wall and windows on the second story. There are guards shooting at you from the windows above. Now incase you hadn't noticed this is Doom and not real 3D - any bodies look the same from all angles when you walk around them and you shoot on the first floor and hit guards on the second. So out the door and straft left and it's generally best to run that way to the end and go in the further doorway from you. Kill the guards and imps, start by shooting the trashcans from the doorway then anything that's still alive after they all explode. At the far end of the room go up the stairs you'll find  some white suits to avoid for now (you'll need them later) a round hallway with a roundhouse in the middle (full of imps and the blue key card). There are some guards in the hallway - kill them before they get you, don't get near the doors of the center roundhouse yet. Pass by it to the first opening on the right, bear right down the hallway and kill the guard. Get the stuff at the end, turn around and go back killing any guards that show up. Bear left out of the hallway and shoot the guards that appear to your right as you go down the hallway. This hallway makes its way all the way around the center roundhouse and the hallways off it are where the guards were shooting at you when you first came out. Make your way to the end of the hallway and go left, then right, shooting guards. You'll see a guard on a level above you, bear left along the wall after killing him and your likely to find some more guards by the stairs that lead up there. Kill them and to up to the right and left collecting the stuff there then back the way you came killing any guards that show up heading across to the area you passed to get here. This will change quickly and require a lot of shooting as the imps and guards come down on the odd shaped lift from above. Seemed different on the Gameboy Advanced - seemed more like a maze with the imps and  guards in it where the walls come down with the stuff on them.

Map 5: Phobos Lab
Run across the green goo (it drops health the longer your on it), shooting to right. Down the hall to the right and up the stairs to the left, killing all the guards & imps - don't stand with your back to the window either put your back to the wall just passed the window looking at the trashcan and shoot it. With all the creatures killed go across to where the trashcan was and push on the wall to open a secret area and collect the stuff there. Then back out, down the stairs to the left and down the hall, go left in to the little area there shooting the things that shoot at you, collect the stuff (going out on this little platform adds a walkway to the room you just came from). Then out and back down the hallway the way you came and back up the stairs, through that room to the new grey metal walkway and down it to a room to shoot the stuff on the other side of the partition. Collect any stuff you can get after killing what you can then back the way you came to the final door across from the area you entered this level. Shoot guards on the walkways to the left and right.

Map 6: Central Processing
Again you need to collect all the key cards and get through a tricky maze.

Episode 4: Thy Flesh Consumed
This map is only available in The Ultimate Doom, which may be installed through a downloadable upgrade patch.