Developer notes allude to an unused ending to Half-Life 1 in which, rather than offering "a battle [the player] has no chance of winning,” the G-Man invites Gordon to his Bible study. A recreation based on leaked material is pictured below.
In the declining weeks of Half-Life 2’s development, as many team members faced malnourishment, Gabe Newell brought in a large Party Burger to appease his staff. According to several employees, it “smelled like victory and tasted like a lobster raised in an ocean of gasoline.”
Alongside Opposing Force and Blue Shift, a 3rd Expansion Pack was planned for Valve's Half-Life titled: G. This expansion was meant to explore the backstory of the enigmatic G-Man, but was shut down by Valve due to creative differences with Gearbox.
Gabe Newell acquired the rights to the Defense of the Ancients IP thinking that it was a training program designed to help him protect his grandmother’s nursing home from goons. After Valve employees explained that it was a game, he reluctantly approved the now acclaimed Dota 2.
While working on an update for Day of Defeat: Source, an anonymous employee began adding outlandish weapons to the Axis team, such as rayguns and flying saucers. When he was caught in the act, he tried to reason that he "saw it on the History Channel."
In 2014, Valve initiated a program in which volunteering Steam users could market the Steam Machine to previously uncontacted hunter-gatherer tribes, with a special discount on games as a reward. This was quickly aborted after one volunteer was found dead in a ditch.
While designing levels for Portal 2, Dario Casali was informed that his idea to "give the player a big ol' machine gun" (as quoted from his whiteboard pitch) was rejected. This sent him into a frenzy, shouting "I am the king of Valve Software!" until being sedated.
Counter-Strike is known for having many maps that were cut prior to its retail release. One of these, de_space, proved to be extremely unpopular with players as both teams would quickly die from explosive decompression due to the game's lack of a space suit.
When analyzed, many Half-Life 2 levels subtly encourage the player to drown themselves. This is done with a technique called “leading lines,” which directs players towards certain areas, such as sticking their head into the ocean until they strangle themselves in the murky water.
In one iteration of the Half-Life 2 storyline, the Air Exchange was replaced by the "Funfair Exchange", a Combine-operated amusement park complete with Ferris wheels and various tents. After some thought, it was erased due to conflicting with the overall tone of the game.
Due to diminishing food supplies at Valve in 2005, a band of rogue employees barricaded themselves in the cafeteria. Gabe Newell tried to end the mutiny by dialing the authorities, where he was reportedly heard shouting "Send in the Ghostbusters! And James Bond!" over the phone.
Left 4 Dead 2's Jockey originated from the concept of infected animals, one of which was a chimpanzee. After a few demonstrations, they were deemed "too implausible." However, the gameplay behavior of the zombie chimp was kept, repurposed to fit a new, fun-sized Special Infected.
Prior to the cancellation of the GameCube port of Half-Life, an exclusive singleplayer campaign was planned. Titled Half-Life: Chain Reaction, players would have assumed the role of Peter Mash, a janitor who must unclog the many toilets of Black Mesa with his trusty plunger.
“Gabe Newell often calls colleagues who do poorly on employee evaluations into his office for a ‘friendly game of Dota 2’. We’re not supposed to talk about it.”
-Anonymous Source
“I’m really not sure what’s up with Marc lately. He just showed up at the office with a new, egg shape. He keeps bellowing ‘It’s not Laidlaw anymore!’ during writing seminars. I think he wants to reimplement the Air Exchange.”
-Adrian Finol
Late in Left 4 Dead 2's development, a secret fifth Survivor was removed following an extensive battle in the offices over what their name should be. "Chet's faction chanted ‘His name's not Jack!’ as they threw cups at us. It was unbelievable." stated developer Matt T. Wood.