Invasion... Level 1: Contamination


Invasion... Level 1: Contamination
The starting areaThe starting area
Authors Andy Chen, Claude Martins
Port Vanilla Doom
Year 1994
Link Doomworld/idgames
This level occupies the map slot E1M1. For other maps which occupy this slot, see Category:E1M1.
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Invasion... Level 1: Contamination is a single-level PWAD for Doom that was released in 1994. It was designed by Andy Chen and Claude Martins, and includes a custom music track. It is set around an space station invaded by demons, with strong use of techbase map tropes. It was followed by Invasion... Level 2: The Upper Decks.


Map of Invasion... Level 1: Contamination
Letters in italics refer to marked spots on the map. Sector, thing, and linedef numbers in boldface are secrets which count toward the end-of-level tally.


Other points of interest[edit]


  1. Go through the first door and turn right. Near the first armor bonus you reach are two alcoves. Pressing the western one opens up a secret door opposite leading to a passage with a shotgun guy and two health bonuses (on medium and hard skills only), and a megaarmor which lies on a teleporter to the south-east area. Both the passage to the teleporter and the teleporter itself count as secrets. (sector 27)
  2. See #1. It is not possible to receive credit for this secret as the player teleports before stepping on the sector. (sector 28)
  3. From the blue key, head east then south. Continue through a fake wall, at the end of which is a soul sphere. (sector 118)
  4. Heading north from the blue key area, there are two passages to the west. Between them is a fake wall, through which is a partial invisibility and a lift leading up to a berserk. (sector 122)
  5. The room with the teleporters leading to the red key area has a secret door on its north wall leading via a second door and a lift to the yellow key and a box of shells. Both the sector between the doors and the yellow key sector count as secrets. (sector 256)
  6. See #5. (sector 179)
  7. Head north from the blue key area then turn right at the end and right at the end of that path. Immediately on the left is a fake wall through which is a shotgun guy on a platform (on medium and hard skills) and a nukage pit down below, which contains a chainsaw as well as (on medium and hard skills) a medikit and a spectre (two on hard skill). There is a switch which causes the platform to lower, allowing you to jump across and out of this area. Note that entering this area activates a crushing ceiling. (sector 285)


Because one secret cannot be achieved (see Secrets section), the maximum secrets percentage obtainable is 85%.

If the player goes through the teleporter in Secret #2, he will be stuck in the south-east area unless he both has the red key and has pressed the switch near the computer map.

Demo files[edit]

This WAD features three built-in demos by the authors. All require Doom v1.2 to view them. The demos are:

Demo Skill Tics Length
DEMO1 3 3528 1:40.80
DEMO2 3 9820 4:40.57
DEMO3 3 16875 8:02.14

Areas / screenshots[edit]


Routes and tricks[edit]

Current records[edit]

The records for the map at the Doom Speed Demo Archive are:

Run Time Player Date File Notes
UV speed 3:56.43 Serge Marudov (Never_Again) 2014-03-26
NM speed
UV max 14:49.03 Serge Marudov (Never_Again) 2014-03-26
NM 100S
UV -fast
UV -respawn
UV Tyson
UV pacifist

The data was last verified in its entirety on November 30, 2021.


Player spawns[edit]

This level contains thirteen spawn points:

  1. facing south. (thing 227)
  2. facing north. (thing 228)
  3. facing south. (thing 229)
  4. facing south. (thing 230)
  5. facing south. (thing 231)
  6. facing north-west. (thing 232)
  7. facing south-east. (thing 233)
  8. facing west. (thing 234)
  9. facing west. (thing 235)
  10. facing south. (thing 236)
  11. facing north. (thing 237)
  12. facing south-east. (thing 555)
  13. facing north-west. (thing 568)


Map data[edit]

Things 671
Vertices 1519*
Linedefs 1720
Sidedefs 2417
Sectors 389
* The vertex count without the effect of node building is 1347.


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

Technical information[edit]

Inspiration and development[edit]


See also[edit]


External links[edit]