Margaret Atwood once wrote, “The best way of keeping a secret is to pretend there isn't one.” In video games, it may seem like you, the player, have found everything there was to find within your favorite game, however, there will always be that one elusive treasure that escaped your eyes the first time around. Whether it’s a high-level weapon, exotic costume, hidden dialogue, or a brand new area to explore, video game developers are incredibly clever when it comes to creating secrets. If anybody knew how to keep a secret, it would be them.

The best video game secrets are the ones that are hidden in plain sight. Secrets that can’t be uncovered by simply entering the Konami Code, or found by skimming through a game’s GameFAQs walkthrough. No, the secrets we’ll be talking about today are the ones that were so well hidden it took years for players to find them. Yes, secrets so hard to find it was like the developers never wanted anyone to find them at all. Some of these secrets would have never been documented if not for the painstaking efforts of data miners, trial and error playthroughs by hardcore gamers, or subtle hints delivered by former game developers.

Ranging from a hidden birthday message in a popular first-person sci-fi shooter to a risqué minigame that sparked public outcry to an already controversial game, here are 15 secrets in video games they never wanted us to find.

Remember now: This list is a secret to everybody.

15 Mike Tyson's Punch Out: How To Knock Out The Champ

Punch Out Mike Tyson

Punch Out is not a game to be underestimated. Sure, on the surface, it looks like a simple boxing game featuring a colorful worldwide cast and that one ear-biter from The Hangover, however, the game demands precise timing and stamina. Those boxers won't go down easy, so you have to make every punch count. What many players may not know is that the game actually clues you in on when to deliver a finishing blow to your larger-than-life opponents.

During your first fight with Piston Honda, or your second fight with Bald Bull, a bearded audience member will duck/nod at the exact moment you can deliver a knockout punch.

There's another animation cue involving Bald Bull and flash photography. Game designer, Makoto Wada, revealed this long undiscovered easter egg in the Iwata Asks interview for Punch Out.

"This is a great opportunity, so I have something I'd like to say," Wada said. "In Punch-Out!!, the game gives you a lot of hints about effective timing of punches. There is a big boxer called Bald Bull in the NES version as well and a light flashes to the right in the audience when he charges. If you punch when it flashes you will land a body blow."

14 The Apprentice: Nudality

via youtube.com

The Philips CD-i system will go down as one of the worst video game systems ever released. The system was so bad not even Nintendo and its key franchises like Mario and Zelda could save it, although, that was likely because those CD-i Nintendo games turned out to be trash. If nothing else, it's a system that will be remembered for sneaking anime nudes in a kid's game.

Yup, if you thought Grand Theft Auto was the first game to push the boundaries, you're in for a rude awakening. The Apprentice - a game completely unrelated to the NBC show formerly starring our reality-star president - featured a string of codes that would allow the player to undress the anime-ish female character on the title screen.

How did this saucy secret stay hidden from everyone - including the game-hating politicians? Well, it was a CD-i game. Self-explanatory, really.

13 Serious Sam: Play As A Pacifist

Serious Sam Pacifist
via dualshockers.com

Serious Sam is a game about a simple man on a journey for peace... a journey for peace by blowing up every living thing in sight. What you may not know about this 15-year-old game is that for one level you can actually skip the "shoot first and ask questions later" approach to the game for something less violent. That's right, it's entirely possible to play a level in Serious Sam without killing anything at all.

As demonstrated in the video below, the level Sacred Yards - which is itself a secret level - can be completed by forgoing the shooting and instead solve a series of puzzles hidden throughout the area.

The discovery of this double secret was only made possible when SolaisYosei was hired by the game's developer, Croteam, and asked CEO Roman Ribaric about any undiscovered secrets in Secret Sam. Ribaric, who happened to be the design lead on the game, teased its existence by telling SolaisYosei to load up the Serious Sam level editor and see what he could find in Sacred Yards. The rest is history.

Link to the Past Secret Room
via youtube.com

For any 90s kid growing up with Nintendo, there's no prize sweeter than having your very own name appear in a Nintendo video game. That was the case for Chris Houlihan, a kid who won a Nintendo Power contest to get his or her name in an upcoming NES game. While Chris's name didn't actually appear in any NES games, it did appear in one of most acclaimed Super Nintendo games of all time: The Legend of Zelda: A Link to the Past.

The Chris Houlihan Room is actually a debug room for whenever the game can't pinpoint Link's position on the Y-axis field. A failsafe room for the player, to explain things more simply. Which is why the only way to access the room is to act out a variety of glitches to clip out of the overworld. One popular method is to use the Pegasus Boots to dash from the Sanctuary area to the Sewer Passageway's entrance, which if executed correctly, will send Link spiraling down the hidden room.

The room itself has 45 Blue Rupees placed throughout the floor and a Telepathy Tile that reads "My name is Chris Houlihan. This is my top secret room. Keep it between us, OK?"

11 Shenmue II: Underground Duck Racing

Shenmue II Duck Racing
via shenmuedojo.net

Two years ago the Shenmue 3 Kickstarter broke the record for the most funded game on the site by accumulating over $6.3 million. As impressive as that feat is, one could only imagine how higher the funds would have been if series creator Yu Suzuki included the Duck Racing minigame from Shenmue 2 as a stretch goal. That's potential billions lost... probably.

It just wouldn't be a Shenmue game if your quest to avenge your father's death was distracted by a bizarre minigame like gambling on which duck is the fastest. It certainly wouldn't fit the criteria for a Shenmue game if the method for activating this minigame was straightforward either. To discover the joys of duck racing in Hong Kong, you'll have to to win the Bronze and Silver Medals by defeating Izumi Takano and Eileen M. Edelweiss in the 3rd floor of the Pine Game Arcade. After defeating Izumi, she'll ask you to visit her at the Tomato Convenience Store in Golden Qr, then she'll show you the wonders of duck racing when you press the X button.

10 Splinter Cell: Double Agent: Operation Rescue Seals

Splinter Cell Rescue Seals

When you play a Tom Clancy Splinter Cell game, you expect espionage, realism, and grit. One thing you don't normally expect from a Splinter Cell game is an adorable baby seal named Cookie and yet, that's what the 2006 release of Splinter Cell: Double Agent had to offer for gamers clever enough to unlock it.

In the secret minigame, five baby seals named Cookie, Buddy, Pepperoni, Vanilla, and Muffin are in need of rescuing and Sam Fisher is the only man up to that task. Actually, that's not true, as the mission is available during co-op mode, so you and your friend are actually in charge of rescuing these precious babies.

Accessing this mission requires the player to shoot the locker in the guard's room of Prison A, grab the coin inside and use it in the vending machine found earlier in the level. The first baby seal will be released and he'll ask you to find his friends.

The code went undiscovered four years after the game's release and would have likely remained a mystery if one of the developers Simon Lasalle, Ubisoft Montreal level designer, and his friend, Julien Daunais, didn't spill the beans in the video above.

9 Grand Theft Auto: San Andreas: Hot Coffee Minigame

via youtube.com

Ever since Grand Theft Auto III shifted from the top-down pedestrian violence of past games into a 3D perspective, the franchise continues to be a lightning rod for controversy. In the 2001 release of Grand Theft Auto: San Andreas, what pushed politicians over the edge wasn't the game's excessive violence, but it's hidden sex minigame dubbed "Hot Coffee."

The Hot Coffee minigame involves the game's main character, Carl "CJ" Johnson, in a crudely-animated and interactive sex scene with one of his six possible girlfriends. Its name derives from CJ's girlfriend inviting him over for some "hot coffee" before the minigame, which is a popular euphemism for sex.

Despite publisher Rockstar disabling the sexy minigame for public release, modders discovered its existence once the game became available on PC and turned it back on. Needless to say, once word got out that a Grand Theft Auto game had a full-fledged sex minigame, the politicians raised hell.

Rockstar claimed the Hot Coffee minigame was the work of hackers, however, the minigame is hidden in the PS2 and Xbox versions of the game as well. Following stories of the game being pulled from shelves and re-rated to Adults Only, Rockstar released a clean version of San Andreas that removed the controversial minigame completely, along with a patch labeled "Cold Coffee" that disables the minigame for PC.

8 Batman: Arkham Asylum: Arkham City Plans

Arkham Asylum Batman

With the Batman franchise being the money-maker that it is, it's not hard to see why Rocksteady, the developers behind Batman: Arkham Asylum, would have planned a sequel to their critically-acclaimed game in advanced. Little did we know how far talks of Batman: Arkham City were during the development of Arkham Asylum. As seen in the video below, a secret room containing blueprints for Arkham City was hidden deviously well in the game.

It's not viewable on the map; it can't be detected with Batman's detective mode, and you'll need to use three explosive gels to crack open the wall, where normally you would only use one. Game Informer asked Paul Crocker, Rocksteady Studios lead narrative designer, about how the team managed to keep this easter egg hidden from the internet.

"From the beginning we knew that Quincy was a bad guy, and planned what his next move would be. The room obviously ties into Arkham City, but to be fair, we hid it pretty well. We did assume that it would be found eventually and after following forum posts for 6 months or so, decided to announce it in the ‘Game of the Year’ podcast."

7 Wave Race: Blue Storm: Jerkass Announcer

Wave Race Announcer Jerkass
via logos.wikia.com.

It took nine years after the release of Wave Race: Blue Storms on the Nintendo GameCube for gamers to discover this peculiar easter egg. The announcer for the jet ski racing game is usually upbeat and encouraging; getting emotionally invested whenever a player goes turbo towards the finish line. However, there is a way to change this one helpful commentator into one that's a complete jerk.

NeoGAF user RaoulDuke discovered that by entering in an elaborate sequence of button presses, you can turn the cheerful announcer into an asshole. No longer will you hear informative commentary; only insults.

The deadpan deliveries are soul-crushingly amusing. It's hard to pick a favorite. "You don't have an inferiority complex. You're just inferior." Ouch. "You must have a sixth sense, because there's no sign of the other five." Oof. "Your wins are like diamonds—very rare." Damn. It's no wonder why the developers made this secret extra hard to find. No mere man could walk away from serious burns like those.

6 Freddi Fish: Freddi Sacrifices Her Friend

Freddi Fish Die
via youtube.com

Don't let her cutesy appearance fool you. Freddi Fish is one sadistic yellow fish. For evidenced please turn to Freddi Fish and the Case of the Missing Kelp Seeds, the 1994 computer adventure game by Humongous Entertainment. While the adorable-looking game may appear to be a great way to educate the youngins on math and stuff, Freddi is far more disturbing than its initial impression has led on. Just take a look at Freddi sacrificing her best friend Luther to this hungry eel.

Originally, you're supposed to offer the villainous eel a simple sandwich, but Freddi had a more sinister solution in mind.

In fairness, the hidden cutscene can only be obtained by messing with the game's files. Tom Verre, the animator behind the gruesome scene, created it as a way of blowing off steam during development. Interestingly, the scene is fully-voiced by the game's cast and is also available in foreign languages.

5 Halo 3: Secret Happy Birthday Message

Halo 3 Happy Birthday
via nowgamer.com.

Imagine waiting seven years for a happy birthday message from your loved one.

Adrian Perez, a programmer at Bungie, hid a happy birthday message to his wife, Laura, in the third and final installment of the original Halo trilogy. By setting the date to December 25 from the console dashboard (while disconnected from Xbox Live), booting up Halo 3 and starting the campaign mission, and holding down both thumbsticks when the loading screen begins, the message will appear. The message, "Happy Birthday, Lauren!", becomes clear as the Halo ring pans out onscreen.

It took dedicated Halo players years to uncover Perez's message. Bungie engineer Jon Cable alluded to the secret message in a 2012 mailbag, and Perez provided a clue to the community a month later. Thankfully, Perez didn't wait for Halo players to uncover the happy birthday message before showing it to his wife, as he said his proudest moment at Bungie was "showing my wife the easter egg I put in the Halo 3 loading screen for her — the one that nobody has found yet."

4 Goldeneye: Line Mode

Goldeneye Line Mode
Via Youtube.com

Before there were Halo and Call of Duty, the 1997 video game adaptation of Goldeneye defined the first-person shooter genre on the Nintendo 64. Based on the 1995 James Bond film starring Pierce Brosnan - the first, to be exact - the spy shooter by former Nintendo developer Rare laid out the template for more realistic and atmospheric shooters on gaming consoles. Quite the accomplishment for an inexperienced team at the time; not counting the last-minute multiplayer that took the game to legendary status.

Goldeneye featured a grand total of 23 cheats accessible to players, such as invincibility, invisibility, unlimited ammo, and, of course, big head mode. All standard stuff you would expect from a 90s video game. However, there is one cheat that didn't make the final cut, at least properly. By pressing a series of buttons on the N64 controller, a 24th cheat code labeled Line Mode will activate and strip the game of all colors and textures.

One look at the video and it becomes obvious why Line Mode was never officially available in the game. It's nearly impossible to see what's happening onscreen; acting more as a detriment to the player than a cool reward. As one of the developers said, "The cheats were devised to try and make the game more fun in both the single and multiplayer games. How a line mode would have done this eluded us, so we kept it out."

3 Super Smash Bros. Melee: Play as Master Hand

Super Smash Bros. Melee Master Hand
via Youtube.com

Super Smash Bros. games have come and gone, but Super Smash Bros. Melee - the 2001 launch game for the Nintendo GameCube - remains the most popular entry in the series. The competitive fighting scene, in particular, is responsible for keeping this 16-year-old game in the limelight with record-shattering performances at EVO and other fighting game tournaments alike. While Super Smash Bros. Melee requires a certain set of rule to play competitively as other fighting games, such as limiting the use of stages and playable characters, one character that's definitely not fair play is the selection of Master Hand, the all-powerful final boss of the franchise.

Activating the Master Hand glitch is no easy task. A GameCube controller will need to be plugged into the system's third port. You'll then have to point your cursor over the name field on the character select screen and hold A and B. Then, you must release A while holding B. Finally, scroll down to the Name Entry field, and press A again while still holding B down. If done successfully, you be able to play as the crazy glove himself, however, he can only be controlled by player three.

The biggest pro to using Master Hand is that he's not designed to be K.O., meaning your opponent will have to sustain less damage than you in an eight-minute match in order to win. On the downside, Master Hand was never designed to be a playable character, so his move sets are terribly long-winded and he cannot guard nor dodge attacks.

2 Mortal Kombat: Accessing the Hidden Diagnostic Menus

Mortal Kombat Arcade
via commons.wikimedia.org.

Arcades are hard to come by these days, but back in the 90s games like Mortal Kombat made sure every chained pizzeria had at least one, so players could empty their pocket change into (Who wouldn't want to dump their quarters into a game where you could rip your opponent's spinal cord out?). As a matter of fact, the limited availability of today's arcade systems explains why this cheat took over 20 years to discover.

The EJB menus - named after Mortal Kombat co-creator Ed Boon - allows the players to turn on free play, access the ending to every fighter, display the word "Hello" onscreen, view fatality animations and so much more. This cheat is available in Mortal Kombat 1, 2, 3 and Ultimate Mortal Kombat 3; with MK3 offering a Galaga mini-game as a bonus. How can players access this cheat? It's a real "Test Your Might" challenge, as a number of block buttons will need to be pressed in a specific order.

1 Pokémon: Fight Professor Oak

Pokemon Professor Oak

If you ever wanted to get Professor Oak back for giving you bad advice in Pokémon Red, Blue, and Yellow, here's your chance. It's possible to take on the Pokémon professor by using a Game Shark code or performing game glitches to trigger the lost battle. For an elaborate explanation on how to fight Professor Oak, check out the video below. One important requirement you'll need to meet to activate the battle is having a Pokémon with a 226 SPECIAL stat.

It's unknown why the developers decided players shouldn't go toe-to-toe with the Oak man himself, but based on his high-leveled team, it seems he was intended to be the game's final boss. This theory is backed up by an in-game email on the PC of Professor Oak's Laboratory, where the Indigo League issues a challenge to all Pokémon Trainers and specifically requests Oak to come and visit them.

Oak normally battles with a level 66 Tauros, a level 67 Exeggutor, a level 68 Arcanine, a level 70 Gyarados, and one of the Kanto starter Pokémon at level 69 (nice).