Video game developers spend years building worlds, characters and systems for players to explore. Apparently, somewhere during that process, someone usually decides the game also needs a secret room, a developer’s face hidden on a wall or an extremely elaborate joke that only five players will ever discover naturally.

These hidden surprises are known as Easter eggs. Some are simple references to other games or films. Others require players to perform bizarre sequences of actions, travel to places they were never expected to reach or stare at something completely ordinary until the game suddenly becomes strange.

The best Easter eggs do not improve your character or help you finish the story. They exist because someone on the development team thought it would be funny, mysterious or memorable. These ten examples show just how far developers have taken that idea.

1. Doom II hid John Romero’s head behind the final boss

The final boss of Doom II appears to be an enormous demonic structure known as the Icon of Sin. Players normally defeat it by firing rockets into an exposed opening.

But hidden behind that giant face is something considerably stranger.

Using cheats or other methods to look inside the structure reveals the severed head of designer John Romero mounted on a spike. The game is technically damaging Romero’s hidden head when the player attacks the boss.

There is another joke layered on top of it. At the beginning of the encounter, the boss produces a distorted message. Played backward, it reveals Romero saying that defeating the game requires killing him.

It is exactly the kind of developer joke players were never supposed to see during ordinary gameplay, which is probably why it became legendary.

2. Batman: Arkham Asylum hid the sequel in a secret room

Most Easter eggs reference something that already exists.

Batman: Arkham Asylum hid something that did not officially exist yet.

Inside Warden Quincy Sharp’s office, players could destroy a particular wall and discover a secret room containing plans and documents connected to Arkham City.

The room effectively teased the setting of the game’s eventual sequel, Batman: Arkham City.

What made the secret particularly unusual was how well it was hidden. Players did not immediately discover it after release, and developer Rocksteady eventually revealed its existence.

The studio had placed a clue to its next major game directly inside the previous one and then watched as players walked past it.

For a community famous for searching every suspicious wall, that is almost impressive.

3. Grand Theft Auto: Vice City contained a literal Easter egg

Sometimes developers decide subtlety is overrated.

In Grand Theft Auto: Vice City, players who reach a hidden room can find an enormous chocolate-colored egg sitting on a pedestal.

The egg literally says “Happy Easter.”

There is no complicated metaphor or obscure reference.

It is an Easter egg that is an actual Easter egg.

The joke became one of gaming’s most famous examples of developers taking the term completely literally.

It also perfectly matches the humor of the Grand Theft Auto series, where the developers frequently reward players for exploring places they were never expected to visit.

4. The Witcher 2 punished players for killing too many chickens

Games often allow players to attack animals that have absolutely nothing to do with the main story.

The Witcher series found a memorable way to discourage that behavior.

Kill too many chickens in certain versions of The Witcher 2, and the game can summon an absurdly powerful chicken-like enemy sometimes referred to as the Chicken Coward.

The joke was designed partly as an anti-exploit measure. Players had discovered they could repeatedly kill chickens to collect items and make money.

Instead of simply removing the exploit, the developers created consequences.

Keep attacking harmless chickens and eventually the game sends something much less harmless after you.

It is game balancing through poultry-based intimidation.

5. Diablo III created a rainbow nightmare called Whimsyshire

When early footage of Diablo III appeared, some fans complained that the game looked too colorful compared with the darker visual style of previous entries.

Blizzard responded in the most reasonable possible way.

It created Whimsyshire.

The secret area is filled with bright rainbows, smiling clouds, colorful landscapes and cute creatures. Those creatures can then be violently attacked because, despite the appearance, this is still Diablo.

The area functions as an elaborate joke about the criticism that the game had become too cheerful.

Instead of defending the art direction in another interview, the developers effectively said: you think that was colorful? We’ll show you colorful.

The result became one of the game’s most memorable secret areas.

6. Metal Gear Solid made you physically change controller ports

The original Metal Gear Solid loved breaking the boundary between the game and the person playing it.

The Psycho Mantis boss fight took this particularly far.

The character appears to read the player’s mind, referencing information connected to the console and reacting in ways that seemed impossible when players first encountered him.

Then comes the famous trick.

To prevent Psycho Mantis from anticipating your movements, the game instructs you to physically unplug the controller and connect it to another controller port.

The solution is not inside the fictional world.

It is sitting in your hands.

For players encountering the trick without knowing about it beforehand, it created one of those rare gaming moments where the console itself suddenly seemed involved in the story.

7. Halo 3 hid a birthday message that took years to confirm

Some Easter eggs are hidden behind complicated gameplay.

Others are hidden behind time itself.

Halo 3 contains a secret message that can appear when a player performs a particular action on December 25. Holding specific controller inputs during a loading screen can reveal a birthday message.

The Easter egg was connected to developer Adrian Perez and was reportedly intended as a message for his wife.

What makes the secret remarkable is how long it remained obscure despite millions of people playing the game.

That demonstrates the challenge of hiding anything from gaming communities.

If a secret survives for years, the developer has done an unusually good job.

8. Cyberpunk 2077 lets you find a game developer in a bathroom

Cyberpunk 2077 contains references to games, films, internet culture and the people who made it.

Some are hidden in places where almost nobody would think to look.

One Easter egg involves a developer appearing in an unexpected bathroom-related location through an image or reference placed into the environment.

It is exactly the kind of tiny joke that can survive inside a huge open world because developers know players will eventually investigate almost every corner.

Open-world games are especially good environments for Easter eggs because they contain so many locations that have no direct connection to the main story.

Developers can hide something ridiculous somewhere remote and reasonably expect that eventually one determined player will find it.

9. Fallout: New Vegas made the wasteland even stranger

Fallout: New Vegas already takes place in a world filled with mutants, robots and post-apocalyptic absurdity.

Then there is the Wild Wasteland trait.

Selecting it changes the game by adding unusual encounters and references throughout the world. Players can discover strange skeleton arrangements, unusual characters and jokes inspired by other pieces of popular culture.

One famous encounter references Indiana Jones and the Kingdom of the Crystal Skull by placing a skeleton inside a refrigerator.

The trait essentially gives players permission to experience a slightly less serious version of an already strange world.

Instead of hiding one Easter egg, the developers created an optional system that adds an entire collection of them.

10. Adventure hid the secret that gave Easter eggs their name

The most important video game Easter egg is also one of the earliest.

Atari’s Adventure, released in 1980, contained a hidden room displaying the message “Created by Warren Robinett.”

At the time, Atari generally did not publicly credit individual developers in its games.

Robinett secretly added his own credit.

Players had to find a tiny hidden object and carry it through a particular sequence before accessing the secret room.

After the message was discovered, Atari chose not to remove it. The hidden surprise was compared to finding an Easter egg, helping popularize the term that gaming still uses today.

What began partly as a developer quietly insisting on receiving credit became a tradition lasting decades.

Easter eggs reward people who refuse to play normally

The strangest thing about video game Easter eggs is the amount of effort developers sometimes spend creating content most players will never see.

Someone has to design the secret room, program the strange interaction, create the hidden object and test the entire thing.

From a purely practical perspective, it can seem unnecessary.

But games are not purely practical objects.

Easter eggs create a private conversation between developers and unusually curious players. They reward people who check behind suspicious walls, revisit old areas and ask what happens if they do something nobody sensible would attempt.

Most players follow the path the game gives them.

Easter egg hunters look at that path and immediately wonder what the developers hid somewhere else.

And every once in a while, the answer is the head of John Romero on a spike.