Doom
Episode One:  Knee Deep in the Dead
Secrets

Level One:  "Hangar"  (3 secrets)
1.  After you cross the zigzag path across the green ooze, there is a
secret door on the right side which leads outside to the Blue Armor.
2.  After you go through the door just before the "Exit", go back out 
to where the two imps were up on the platform.  The platform has
lowered and there is a room behind it.
3.  After you explore #2, go back out to the computer room.  Run back
to the same room and you'll notice an opening in the left wall.  A
platform will lift you up to a secret passageway.

Level Two:  "Nuclear Plant"  (6 secrets)
1.  Going to the right from the beginning, there is a secret door on
the left wall which contains Green Armor, a backpack, first aid kit,
and a switch (It opens the door to the outside courtyard through the
left door and up the stairs).
2.  To the right after going through the red door there is a switch
on back of the column on the island in the green ooze.  (It opens up
the computer area).
3.  In the computer area, shoot at the wall behind the Green Armor
after you kill the imps, of course.
4.  After you get the chainsaw, check the left side of the wall in the
hallway on your way back down the stairs.
5.  At the other end of the computer area, there is a secret door
between two silver stripes on the wall.  Watch out for the two former
humans!
6.  After you cross the switchback path through the green slime, you'll
see three first aid kits.  There is a secret door on the left wall
before the elevator.

Level Three:  "Toxin Refinery"  (7 secrets)
1.  After you waste the multitude of imps and former humans in the room
on the left side,  kill the monsters that are down in the lower level
through the window.  Go around to the right and go downstairs.  Around
to the left there is a switch on the wall.  It opens up a stairway to
the computer room.  After you kill all the monsters in the computer room
and get the yellow key, go back down the stairs.  There are two secret
areas in the computer room.  Run as fast as you can up the stairs and go
to the left, you will see a section of wall that is open.  Run into it
and kill the three imps that are down the stairs.  Go all the way into
the room, throw the switch on the back of the column to get your
supercharge (Happy face!).
2.  After you get the supercharge, go back up the stairs and run
straight out to the other secret area that is almost to the other corner
on the left.  After you kill the three imps in there, pick up your
rocket launcher.
3.  From the same area, you will see a tunnel in the ooze on the right
side.  Jump in and follow the ooze to a platform.  Throw the switch.
There's a secret door to the right of the switch.
4.  The next secret is in the pit of green ooze.  It's a switch that
raises the center portion, so jump in there and throw the switch, after
you kill all the monsters.
5.  After you go through the blue key door, you will see two blue
archways.  There's a secret door just before the arch to the right on
the right side.
6.  Before you go to the "Exit", go back to the beginning of the level
and you will see a bridge has risen across the pit of green ooze.  When
you walk up to the door it will open automatically.
7.  After the two panels open letting the four imps loose on you, go
through the door at the center.  When you get to the room with the
switch, you can open the rear wall and ride up to get a box of rockets.
The switch leads to the secret level.

Secret Level:  "Military Base"  (4 secrets)
1.  Inside the Red door, you'll see a passageway at the left rear.
Shoot the barrels and throw the switch.  The wall outside will open
releasing some demons.  Once they are dead you can go upstairs to get
the blue key.
2.  Inside the Blue door, the middle of the right wall will open.
3.  In the room with the torches, go to the left front corner and an
elevator will lower you to a green ooze filled area.  Run across and
pick-up the ammo.
4.  Leave #3 by running to the other side and another platform will
lower.

Level Four:  "Command Control"  (3  secrets)
1.  In the first room there is a secret room on the left wall.
2.  Go to the left in the trench of green slime.  You'll find one former
human sergeant, plenty of goodies, and a elevator that I couldn't get to
work.
3.  The other end of the slime trench has a elevator platform and a
switch.

Level Five:  "Phobos Lab"  (8  secrets)
1.  Cross the slime river, kill the monsters, and go down the hallway to
the right.  You'll come out on a balcony surrounded by green ooze.  You
will see the bridge rising in front of you.
2.  Go back down the hallway to the set of stairs on the right.  Go up
the stairs and shoot the two barrels.  There's a secret door behind the
barrels.
3.  Go across bridge to get the yellow key.  After you get the yellow
key, and get to the bridge, look down at the area between the balcony
and the outside wall.  You should notice an area of wall that is more
brown than green.  Jump in and push on the area of the wall.  You'll
come out in the main hallway.
4 and 5.  After you go through the yellow door and survive all the
monsters, you'll see a first aid kit in a small alcove on the outside
wall.  Open the wall and get the radiation suit.  It's probably better
to cross the ooze now and push the switch.  Also after the columns
descend, go to the right one and ride it up.  Run off the column to get
the Blue Armor.  Go back to where you got the radiation suit.  There's
two more secret doors that lead outside to a supercharge.
6.  In the computer room, just to the right of the switch, there's a
secret door.  Room contains lots of goodies, including a computer map.
7.  In the dark area near the exit, part of the middle wall of the room
will go up if you push on it.
8.  Once you get the blue keycard, go back to the yellow door.  Open the
door, take the elevator down, and go to the right.  To your front you
will see the platform where the imp was originally.  This platform will
go up and down.  If it is already up, continue down the passage until
you hear the sound of the platform lowering and run back to get on it.
Once you get raised, open the right wall twice.  You will see a secret
door straight ahead of you that leads to the passage outside the yellow
door.  If you go to the left you will see a red star on the floor.  If
you step on it you will be transported out to the main hallway at the
beginning of the level.  If you pass the star you will see another
secret door that will lead to the darkened "Exit" area.

Level Six:  "Central Processing" (4 secrets)
1.  Go through the red door to get the blue key.  If you look down from
where the blue key was, you will see an opening in the wall down in the 
ooze.  I think there is a radiation suit around to your right.  After
you come back out of the opening in the wall stay to the right and a 
passage will lead you back out.
2.  In the computer area, go through the doorway to the right.  After
you kill the imps up on the platform and behind the screen, go straight
ahead towards the blue door.  Turn around and go back and on the left
you will see where the platform has lowered.  More baddies will come
out.  Cross the ooze.  There's a secret door on the back wall that
leads to the yellow keycard.
3.  After you get the yellow keycard and get back out to the path that
leads to the blue door, you should be able to see a hidden ooze channel
on the left side (as you are facing the blue door).  Jump in the ooze
and follow the channel.  The doorway at the end leads outside.
4.  Go outside and look for the happy face.  When it lowers, get on the
platform and wait for it to go up.  When it goes up, there's a secret
door in front of you.

Level Seven:  "Computer Station" (3 secrets)
1.  Once you get all keys, go back to the computer area that has the
window that overlooks the courtyard with the invisibility orb.  You will
see a room in the wall that wasn't there before.  There's a secret door
on the left side wall.
2.  After you pass the blue door and go upstairs, you'll see a platform
that lowers when you get close.  If you get on it and jump off to the
right just before it gets to the top you will end up in the ooze.  You
should see an opening in the wall.  You will find a radiation suit
there.  Also a red switch that opens leading you upstairs.  Upstairs
you will see a switch.  You get back by going back downstairs, turning
right, and going down to the supercharge.  When you walk on the
platform where the supercharge was the wall will open.
3.  If you go back and jump off the column on the other side you will
end up near a shelf with a chaingun and some ammo on it.  To get back
there's a secret door to the right as you face the window you jumped
through.

Level Eight:  "Phobos Anomaly" (1 secret)
1.  On the right side wall at the bottom of the stairs there's a secret
door with a super charge.