One of the greatest joys in gaming is discovering a hidden secret. Whether it be the reward for a player's curiosity or something stumbled upon organically, finding something unexpected is an amazing feeling. While most games use these secrets to hide additional power-ups or weapons, some go above and beyond by hiding entire levels.
Such secret levels have often been the subject of speculation and rumor throughout gaming history. One of the first such rumors concerned the 1980 arcade game Battle Zone, which claimed that it was possible to travel to the volcano in the background. Often, these levels exist to provide fan service or explore concepts that would not have fit within the main game.
8 A Fight With Reptile At The Bottom Of The Pit - Mortal Kombat
Those who played the original Mortal Kombat in Arcades might remember the rare appearance of a mysterious Green Ninja who would occasionally appear before fights with a cryptic message. These messages, once decoded indicated that the player needed to win a double flawless victory on the pit stage, without blocking and while shadows are flying over the moon.
If this is done in the single-player mode, the player is then taken to the bottom of the pit for a fight against the green ninja Reptile. The fight itself can be quite challenging as Reptile combines the move-set of both Scorpion and Sub-Zero, but victory rewards the player with a hefty point bonus.
7 Moo Moo Farm - Diablo II
There are few gaming rumors more notorious than that of the supposed secret cow level in the original Diablo. Supposedly if the player did something to the lone cow in the town of Tristram it would lead them to a hidden stage. When a sequel was created, Blizzard decided to play on these rumors and make players' bovine fantasies a reality.
In Diablo II, after beating the game, players could combine Wirt's leg with the tome of town portal in the Horadric Cube. This would result in the creation of a portal to a secret level called Moo Moo Farm (not to be confused with the racecourse of the same name in Mario Kart 64). In this level, players were attacked by hordes of axe-wielding bipedal cows called hell bovines, as well as a special enemy called the Cow King.
6 It Came From Red Alert!
It Came From Red Alert is the name of a secret campaign in the Command & Conquer: Red Alertexpansion packCounterstrike. This campaign can only be unlocked by holding down shift and clicking on the image of a speaker in the game's main menu.
Taking place after the Allied victory, this campaign saw the player's forces attacked by a horde of giant ants that were the result of some Soviet experiment gone horribly wrong. The campaign is clearly based on the 1989 game It Came From The Desert by Cinemaware, which was itself heavily inspired by the 1954 science fiction movie Them!
5 Aztec and Egyptian - 007 GoldenEye
The classic N64 first-person shooter 007 GoldenEye is known for its many unlockables and secrets. Among these are a pair of hidden extra missions based on classic Bond films. The first, Aztec, can be unlocked by beating every mission on secret agent difficulty. This level is based on the 1979 movie Moonraker and has Bond fighting his way through an Aztec temple. The level is quite challenging, but it allows players the chance to use the moonraker laser as well as face off against classic Bond villain Jaws.
The second unlockable mission, Egyptian, is unlocked by beating all previous levels, including Aztec on 00 Agent difficulty. Based on the 1977 movie The Spy Who Loved Me, this stage has Bond fighting his way through an ancient Egyptian temple, culminating with a boss fight against Baron Samedi. It is also the only single-player level in the game to allow players access to the one-shot kill Golden Gun.
4 The Painted World of Ariamis - Dark Souls
The Souls series is full of all manner of secrets, one of the best of which is in the first Dark Souls. Players traveling through Anor Londo might have noticed a massive painting of a castle set against a snow-capped mountain. If the player goes all the way back to the first room that they started the game in they will find an object called the peculiar doll, which at first glance might not seem to have any function.
However, if brought to the painting, the player will be transported into the Painted World of Ariamis. This challenging hidden world features many unique enemies and an optional boss fight set atop a snowy mountain. Players should be warned though, once they enter the Painted World of Ariamis they will not be able to leave until they find the exit on the other side of the map.
3 Out Of This Dimension - Star Fox
One of the more surreal hidden stages in gaming, Out of this Dimension can only be unlocked from the Route 3 asteroid belt. Players must shoot the second asteroid that they see until it is destroyed, then touch the bird-like creature that emerges. Doing this will transport the player to a stage filled with unusual enemies and trippy imagery.
According to the game's lore, this was the last place where James McCloud was seen before he mysteriously disappeared. The stage culminates with a boss fight against a slot machine that can only be won by getting three 7s in a row, causing it to self-destruct. Doing this causes the game's credits to appear, with players able to shoot at names and job titles. The stage then continues indefinitely, implying that Fox is now forever trapped within this strange place.
2 Cerulean Cave - Pokemon Red/ Blue/ Yellow
After setting out on their Pokemon journey to be the best like no one ever was, beating all 8 gym leaders, taking down team rocket, besting the elite four, smoking their rival, and becoming the champion, most players likely assumed that they had seen everything that the Kanto region had to offer. However, some may remember a cave that they were unable to enter next to Cerulean City.
If the player goes there after finishing the game, they will find the entrance to the cave unblocked. Cerulean Cave is filled with high-level Pokemon, many of which are quite rare and hard to find in the outside world. At the very bottom lies a fight against the legendary Mewtwo, by far the most powerful Pokemon in the game, with a chance to capture him.
1 Wolfenstein Maps - DOOM II: Hell on Earth
By the time DOOM II: Hell on Earth was released in 1994, the series had already become known for having secret levels. Even so, fans were delighted to find that two of the secret levels in DOOM II were actually throwbacks to id Software's previous game Wolfenstein 3D. The first such stage could be accessed from a secret exit in map 15 and saw players confronted by a replica of the first stage of Wolfenstein 3D, albeit with all dogs replaced by demons.
This level possessed two exits. One would bring players back to the main campaign on map 16, and the other lead to another Wolfenstein level. This one was based on the Wolfenstein level of the same name, but with the titular Nazi commander replaced with a fight against a terrifying cyber demon.