1. When you take UZI as Louis, he sometimes can say "This is just like a counterstrike!" Steam\steamapps\common\left 4 dead demo\left4dead\sound\player\survivor\voice\Manager \Takesubmachinegun03.wav -Moki

2. If you listen closely when some zombies are attacking you, they actually say something in english. Though its partly inaudible. THEY CAN TALK -Trigg123

3. "GET TO THE CHOPPER!!" Sounds very similar to Arnold in 'The Predator' Steam\SteamApps\common\left 4 dead demo\left4dead\sound\player\survivor\voice\NamVet\ ArriveChopper02.mp3 -Tails Su

4. Dr.Breen in newspaper Pic -KeRupTion

5. Humming Francis: One Hundred Bottles of Beer on the Wall \left4dead\sound\player\survivor\voice\Biker\Nervo usHumming07.wav Zoey: Final Fantasy Theme 01-03, 04 is the fanfare from FF \left4dead\sound\player\survivor\voice\TeenGir l\NervousHumming01.wav Bill: A hurried and chopped up version of Taps \left4dead\sound\player\survivor\voice\NamVet\Nerv ousHumming01.wav Louis: -Unknown-

6. Corporat

7. There's the box of cereal with TF2 on the back of it. The box says 10 classes when Tf2 Has actually 9. Pic 1, Pic 2 -Vi2peratus, Confirmed by Nightmares

8. Louis says i ain't got time to bleed, which is what Jesse Ventura said in The Predator at one point \left4dead\sound\player\survivor\voice\Manager \ZombieGenericLong14 -L33tfella_H

9. The Orange Box juice is a reference to the Orange Box Pic -SJAAKUZ

10. Shout/Scout Reference? Pic -Jyden, BS_1

11. There are the x-rays similar to the hand on the L4D cover. Pic -mussard

12. Inside the first Fridge of the apartment, the sticker on the inside says "UBERCOLD" in team fortress 2 font, uber-charge reference?. Pic -Gromble, Confirmed by Cukydoh

13. Possible reference to Gabe Newell Pic -Pingu

14. Louis character might be a homage to the character "Ben" from Night of the Living Dead by G. Romero. Link, Pic -mystrdat

15. The Lawn Mower and all the chopped up zombies are clearly a reference of Peter Jackson's Brain Dead(aka Dead Alive). Video -Hackmessah

16. When Francis picks up a second gun, he says "Double my fun!". This is a reference to Serious Sam 1 or 2, when Sam says "Double your gun, double your fun!" when he gets his dual colts. \sound\player\survivor\voice\Biker\TakePistol03 -Lycan_assassin, Confirmed by alucard4824

17. The names on the wall of the church in death toll are the developers of L4D. Pic -Fazer2

18. Some Characters say "groovey" when picking up weapons a reference to Ash in Evil Dead 2: Army of Darkness. -Tarnotti

19. Man Vs tank Achievement is a reference to the event of Tienanmen square. Video

20. The serial number on the back of the car at the end of Blood harvest says "TK-421" which was the storm trooper Han Solo impersonated in A New Hope. Pic -EnsignBlue , Pink Panther

Unconfirmed

1. The train has referrences to the boss infected. No smoking = smoker, Boombox = boomer, and littering = Tank. -secretsantaone, GhostRiderLSOV

2. There is a car with the license plate DE_NUKE a Counter strike map. -Cukydoh

3. Sometimes when weapons are picked up a character might say "groovy! an "Army of Darkness" referenc

4. Candy mountain possible reference to charlie the unicorn (never watched it so i wouldn't know)

Interesting Finds

1. The tank is referred as the "hulk" in some sound files.

2. Infected say partial sentences.

3. In the chopper_pilot sound folder the Hospital_finale_flyout show the pilot feeling sick and infected.

4. Gunshots can be heard in the distance on some maps.

5. Zombie dog sounds might be an indication to a previously planned infected.

6. Zoey has infected hands! Hands!

7. While checking on the files i saw some concept art for another infected, probably removed called "the screamer".

While checking on the files i saw some concept art for another infected, probably removed called "the screamer".

According to developer commentary, the screamer was going to be a strait-jacket-wearing special infected that ran away shortly after it saw you. When it did this, it would scream in the background, causing the hoard to come after you. This feature was later rolled into the Boomer, who was thought to have lackluster abilities (just explode and do some damage to the survivors).