Left 4 Dead 2

Whitaker Model
When you bring Whitaker his cola he will clear the way for you Micheal Bay-style, but you can never actually see Whitaker without noclipping. He shares a similar appearance to the Fallen Survivor.



Hidden Magnum Pistol Text
On the Magnum Pistol's barrel the text "1337 Weapon Industries (yOgi) PWN" and "Made In Shyville" can be read. Also, there doesn't seem to be a hole for the bullets to come out of.



Unused M60 Reload Animation
lY-N7GteB24 The M60 has the same reload animation as the AK-47, but since it can never have any reserve ammo this is never seen.

Hunter Attack
Again, the Hunter was supposed to be able to pounce in first-person view. C-y_8X1ge7c

Fallen Survivor
The Fallen Survivor was going to be included in the base game but was cut. They could be spawned but were very buggy and could cause the game to crash and would occasionally drop invisible items. These unidentifiable pickups seem to be broken versions of items ranging from Molotov Cocktails to Medkits. All these problems were fixed when the Fallen Survivor finally made it into The Passing DLC. ObiPxnaLiQ8

German Version
Due to Germany's squeamish censorship laws, there were many cuts and changes to L4D2.
 * The Riot Infected were initally removed from the game due to depiction of violence towards official authority in German law, they were eventually added back in by an update (minus the "SECURITY" on their armour).
 * Weapons from Counter-Strike: Source spawn.
 * Infected cannot be set on fire and no damage is visible when hit with Explosive Ammo or blown up by Pipe Bombs.
 * L4D1-style pipe bomb deaths.
 * After death, the Infected start fading away almost immediately, usually before they even hit the ground.
 * The textures for the Cricket Bat are censored to remove the blood stains.

Australian Version
The Australian version is similar to the German version, but a little more lenient:
 * The Riot Infected are present and accounted for, but do not count towards the "kill all of the uncommon infected" achievement.
 * Common Infected can be set on fire, but won't actually render any fire on the model - they'll run around waving their arms screaming regardless.
 * L4D1-style pipe bomb deaths.
 * No censorship for the weapon textures.
 * The Cricket Bat has a Southern Cross on the bat and the dates of when Australia has won an event called The Ashes.