In the early 1980s, 15 year old Atari 2600 owner Adam Clayton discovered what is widely considered to be one of gaming’s first Easter eggs. By completing an obscure task in the Atari 2600 game Adventure, Clayton found text that said “Created by Warren Robinett,” which was a means for Robinett to claim credit for the game’s development at a time when game designers received little to no recognition for their work. Clayton notified Atari of the secret text, and its popularity led to the company making Easter eggs standard in its future 2600 games.

Since Adventure, Easter eggs have become a staple for video games. However, with so many secrets stuffed in thousands of different games, some of these Easter eggs take years to find. The five Easter eggs below took years to find, and some may never have been discovered if it wasn’t for the intervention of the game developers.

Batman: Arkham City Tease (Batman: Arkham Asylum)

One Easter egg that may have went undiscovered without its developers spilling the beans is the secret room in Batman: Arkham Asylum. The room itself is hidden behind a wall in the Warden’s Office (that can be destroyed with Batman’s handy explosive gel), and it is filled with references to the sequel, Batman: Arkham City.

Fittingly, Arkham City continued the tradition with Easter eggs that pointed to Scarecrow’s diabolical plan in Batman: Arkham Knight, so perhaps there’s still secrets left to be discovered in Arkham Knight that can give fans an idea of what Rocksteady is working on now.

Chris Houlihan’s Room (The Legend of Zelda: A Link to the Past)

In the fall of 1990, Nintendo Power magazine held a contest where the winner would get their name added to a future Nintendo game. Chris Houlihan won the contest, and his name was added to The Legend of Zelda: A Link to the Past on the Super Nintendo. However, Houlihan’s room remained undiscovered by Easter egg hunters until 2002, when the obscure requirements to access it were deciphered from examining the game’s code.

There are multiple ways to access the Chris Houlihan Easter egg in A Link to the Past, but they all lead to the same room. The room contains 45 blue rupees and some text that says, “My name is Chris Houlihan. This is my top secret room. Keep it between us, OK?” Other versions of A Link to the Past still allow players to access the secret room, but the references to Chris Houlihan are removed.

Happy Birthday, Lauren! (Halo 3)

Halo 3 launched in 2007, but it took nearly seven years before anyone found this particular Easter egg. Even though Bungie hinted at its existence on a couple of different occasions, it wasn’t until YouTube user Lord Zedd uploaded a video about the Easter egg in the summer of 2014 that it became widely known.

The egg itself is a simple happy birthday message to a developer’s wife, spelled out in a holographic Halo ring during one of the game’s loading screens. Like other Easter eggs on this list, accessing it is not really difficult, but requires players to do things they would never think of doing when playing normally. To see the message, players need to make sure that their Xbox 360 console is set to December 25 (assuming it’s not already Christmas when they’re trying to access the Easter egg), and then they have to load up a solo campaign mission while clicking in both thumbsticks. If done correctly, players should be treated to a loading screen that says, “Happy birthday, Lauren!”

Japanese Man (Resident Evil 4)

One of the more recent Easter egg discoveries on this list comes from Resident Evil 4. Discovered 12 years after the game’s original launch, this Easter egg is a low-resolution cutout of what appears to be a Japanese man in a bright green coat imitating a zombie. The Easter egg was first found by a YouTuber named SR212787, but became widely known when another YouTuber, Slippy Slides, decided to explore Resident Evil 4 with an unlocked camera a few months later.

Even though Slippy Slides only found this Easter egg because he was using an unlocked camera, it can still be seen in-game. The outline of the cutout can be seen in some ruins in Chapter 5-4 if players aim at it using a sniper rifle with an enhanced scope, and since there’s never a reason to aim a sniper in that direction, it’s no surprise it went undiscovered for 12 years.

LMD (Donkey Kong)

One of the most famous examples of an Easter egg discovered many years later is in the case of Landon Dyer hiding his initials in the Atari 400 port of Donkey Kong. 26 years after the game’s release, Don Hodges went through the game’s code to discover the steps necessary to display Dyer’s initials. First players need to start a new game and set a high score of 37,xxx, 73,xxx, or 77,xxx. Next they have to kill off all their lives, with their last death being by falling. Finally, players need to set the game’s difficulty level to 4, and if they wait for the title screen to appear again, the initials LMD will appear on the screen.

super smash bros master hand and crazy hand

Besides the examples listed here, one other potential discovery comes to mind. It’s technically more of a glitch than it is an Easter egg, but in Super Smash Bros. Melee players can actually play as Master Hand if they jump through enough hoops. There are a couple of ways to activate the glitch, but both will allow players to use Master Hand and his entire move set in the game. The downside to this glitch is that it makes the game prone to freezing, so players shouldn’t expect to get much mileage out of it.

Which Easter egg listed here is your favorite? Let us know your thoughts in the comments below.