Doom/E1M1: Hangar

Note that all walkthroughs for this game are at Ultra-Violence difficulty level. Any lower difficulty level will obviously be easier and have less enemies, so expect less whilst playing through. Nightmare is too difficult even for a walkthrough.

Mission 1: Hangar
You'll start in a large room with an open section straight ahead. In the corners to your left and right you'll find a health vial. Don't shoot any of the barrels, and go to the room with the staircase to the left. Use your pistol to pick off the shotgun marines, netting you a shotgun and a security vest and some armour bonuses at the top. There's a switch on the right-hand side of the right pillar, which opens a secret door by the windows of the open area you entered the level near. Run through it and you'll be outside. Ignore the opening of the wall on the left and sprint across the slime to grab the combat armour.

You can use your shotgun/pistol to pick off some of the extra enemies around here - some normal marines, some shotgun marines and some Imps will be in the various rooms beyond the openings and you can pick them off from outside. Once you're done, Go down the stairs out here and kill the two shotgun marines. You'll find a medikit and a box of shotgun shells down here. At the end of the tunnel, open the wall and you'll emerge near the end of the level. Finish off any nearby enemies in here and head right, and through the door.

In this room there are two marines on the left for you to kill - blast one of the barrels and the explosion might get rid of them. Clear the room out and grab all the goodies. Before you head through the exit door up ahead, you can backtrack through the level and pick up all the extra items and kill the extra enemies, if you so wish. One secret area that appears when the high platform the Imps were on (in the zig-zag path slime room) lowers has a shotgun marine, a shotgun and a box of shotgun shells in it. Anyway, when you're done, head to the exit door, open it, rip the Imp inside a new one, pick the stuff up and throw the switch to leave the level.

Mission 2: Nuclear Plant
As soon as you start, sprint forwards and kill the two marines in the corridor. Sprint all the way to the end where there is a security vest for you, if you need it. Now, work your way around the room, killing the Imps and marines as you go. Once it's all clear, head up the lift in the centre section of this room to get a shotgun, and check the lift in one of the corners for a medikit and a box of bullets. Now, head around to the side of the centre section facing the side of the room with the two non-keycard doors. You may notice a discoloured wall section next to the light. Open it, and you'll find a secret area. Pick up the security vest in here if you need it, but most importantly, pick up the Backpack! You've now got double ammo capacity. Throw the switch in here, then go back out and through either of the doors.

Go up the stairs, killing as you go, and at the top clear out the room of marines and the Imp, and you can pick up the goodies as well as the red keycard. Facing outside, go back down the left-hand staircase and go through the open wall to outside. Kill the crapload of shotgun marines out here and pick up all their ammo, and grab the Soulsphere. Keep going around, though; at the end you'll find two boxes of bullets and the Chaingun!

Go back to the room you started in, and now you can go through the red keycard door on the left-hand side. Kill the marines and go to the right. In the slime room, kill the Imp, then sprint across the slime to the middle platform. Here, throw the switch. This opens a dark maze section full of enemies. You may wonder why I told you to do this, but the maze is full of ammo and health, plus another security vest and two secret areas. At the far corner of the maze is a wall section between two grey columns - open it to reveal a small room with another Backpack in it. On the right-hand side of the maze (as you're looking into it) is a fading-light room with the security vest in it. However, you can shoot the wall behind it with a gun to open another secret area. Follow the stairs up and kill the marines at the top. Shoot the barrel in the corner to kill the Imp in the side room, and throw the switch to make the central pillar lower and allow you to grab the Chainsaw!

Head back out to the red keycard door, then go straight ahead and up the stairs. The lift to the left goes down to the side room you killed the Imp in, which has a medikit and a box of shotgun shells in it. Go back up and navigate the slime path room, and at the end check the discoloured wall on the left for another secret door which leads down to a ledge above the next room, which is full of Imps, marines and barrels. Clear it out, then go back up and use the lift to grab another box of shotgun shells. At the end of the room, flip the switch to open two doors on either side, and go through either and follow the path around to a staircase leading down to the exit door.

A bit of a sneaky tactic; the exit room is full of marines. Kill them, but watch out for the two Imps in the low section next to the exit switch. Throw the switch to leave the level.

Mission 3: Toxin Refinery
It gets a little harder here. Grab the goodies and open the door. There are lots of enemies in this room; you'll be assailed immediately by an Imp and a shotgun marine, and around the corners there are lots more enemies including two new ones, a Demon and a Spectre (look them up on the enemy page if you don't know what they are). Your new chaingun will help here, otherwise continual pummeling with the shotgun will best them. Once they're all dead grab the goodies and go to the left. Open the door at the end of the path around the central slime pit.

In this next room, quickly blast the central barrel to take out the two marines on either side, and then let the several Imps and marines/shotgun marines come into your field of view and blow them away with your shotgun. There are a lot of them. Head to the window on the right by the stairs, and you can shoot some more Imps and marines from up here. Go around and kill any Imps that come up the stairs, then go down and clear the place out. There's some ammo and armour up the lift, but otherwise go left at the bottom and you'll find a switch. Throw it and head back up. You can open the wall section in the random alcove up here and shoot some enemies in the room beyond, but that's if you choose to go to the secret level or not (it's difficult, but fun). Anyway, go around back to the door and you'll find a wall section has opened, with a long staircase beyond it. At the top, snipe the shotgun zombies and Imps with your weapons, and head up. Clear the place out (there are some more Imps and shotgun marines, as well as a Demon and a Spectre at the back), and grab the goodies. In a small tunnel into the central section of the room you'll find the yellow keycard.

Now go back to the stairs and sprint to the bottom. Wait a bit, then sprint back up and around the central section to the right - a part of the wall up to a lit area of the wall will lower, and you can sprint onto it to access a secret area with some Imps, marines and...the Rocket Launcher! Excellent. Put it away for now, though; only use it in emergencies and/or at long range, as you do not get much ammo for it. Turn back to face the door to the previous room, and you'll notice a tunnel in the slime to the left big enough for you to go through. At the end (it's not far) you'll find a medikit and a Backpack. Throw the switch and then locate the off-colour wall section to the right of it. Open the wall and head through for some more goodies including two boxes of bullets and another chaingun. You can go up the lift for two medikits and access to the section of the level before you entered the dark bit up the stairs. But, turn around and go back through the slime tunnel. When you get to the wall you came in from, open it and sprint along the dark room to the right. The end wall will be doing the same thing as the one you just came through, and by getting on it you'll be able to access another secret area.

Down the stairs in here, kill the three Imps, and in the dark room at the end you can throw a switch on the pillar and make it drop to obtain a Soulsphere! This secret region is now exhausted, so go back up the stairs and through the dark room down to the door leading to the starting slime pit room. You'll now want to go all the way to the end where the other door is and go through it. Head through this entire next section of the level, killing all the marines, Imps and Demons as you go (be careful not to fall into the slime when you're outside). At the end, you'll find the blue keycard. Run onto it backwards - this will allow you to already be facing the enemies that come out of a wall section when the lights go out. Kill the four Imps, and head back through the level to the starting slime pit room.

You now have a choice. The raised platform allows you to access a secret wall section at the far end of the slime pit which leads to the secret exit of the level. If you do, simply follow that path to the end (you'll have to escape another monster ambush). If you go to the "proper" exit you'll not go to the secret level, not to mention having to tear through a lot more enemies (loads of shotgun marines and imps). This guide will assume you go to the secret level, as you go to level 4 once you complete it anyway. Head across the platform and open the wall at the end. Kill the Imps and the Demon, and head through to the exit door. Before throwing the switch, check the lift, as you can go up to a platform overlooking a previous section of the level which has a box of rockets on it.

Secret Mission: Military Base
This level is insane! From the start, head to just before you get to the outside section. You'll find a load of imps in a cage in the centre of the courtyard, as well as a load of shotgun marines and normal marines emerging from the four staircases on all sides. Clear the place out, and head down the at the far end of the courtyard opposite you. Kill the Imps, shotgun marines and Spectres down here, pick up the goodies, and head down the lift to kill some more Imps and pick up some more goodies. Head back up to the courtyard and down the staircase next to the corridor you started in. Down here, kill the Imps and Demons and pick up the yellow keycard. The room accessible to the side has another rocket launcher and a box of rockets, so sprint to get it, then sprint around the outside of the room and wait at the top of the stairs with your shotgun. A crapload of enemies will teleport in on the star section, so pick them all off as they arrive. Once they're all dead, go down either of the other two staircases in the courtyard, and use the yellow keycard door accessible from them. Inside, kill the enemies and grab the red keycard, then kill the Imps and shotgun marines that come out from the wall section behind where the keycard was.

Now, run back across the room with the large block in the middle (one of the rooms off the courtyard). Go through the red keycard door, and kill all the enemies on the other side. Go around to the small tunnel at the back of the room, clear out the barrels, and throw the switch. This will trigger a side corridor to open, and the block in the previous room to lower, revealing the blue keycard and a ton of Demons. Kill them all, and grab the keycard. You can now go through the blue keycard door accessible from one of the staircases off the courtyard.

Inside this next room, kill the 4 Spectres on your side of the room, then kill the shotgun marines and Imps across the slime chasm. Use the discoloured wall section on the right to access a secret room - sprint down the staircase and across the room to the lowered platform at the end - if you're not quick enough you have to repeat it. Once up, make short sprinting jumps down the columns in turn to pick up all the goodies. Now, head back to the slime chasm room and delibarately drop down into it; follow the tunnel, and kill the Imp on the platform. Throw the switch, then head through the secret door when it opens to the lift at the end. Go up it (ignore the Imps down here; you can't fight all of them whilst on the slime) and you can go across the raised platform to the exit switch (kill any Spectres that appear).