History Main / SecretLevel

** ''[[{{SuperMarioBrosTheLostLevels}} Super Mario Bros.: The Lost Levels]]'' has World 9, which could only be accessed by playing the first eight worlds without warping.

* ''WarioLand'', almost every game in the series has many secret levels, including whole secret worlds.

* Two words: [[SuperMarioGalaxy Hungry]] [[SuperMarioGalaxy2 Lumas.]]

** ''[[LuigisMansion Luigi's Mansion]]'' has multiple hidden, secret, or otherwise-unneeded rooms inside the game, which are essential for 100% completion and getting all of the ghosts, but is often entirely optional and one may even forget to do them as they play due to the fact they're never mentioned.

* Not sure if this is a SecretLevel or a DummiedOut thing, but in ''ZeldaIITheAdventureOfLink'', you can go to Darunia and climb on top of houses. If you go to a roof nearest the top of the screen, you can jump off-screen with the JUMP spell, then (while still off-screen) use the FAIRY spell and fly up. You'll get the animation for falling down a hole and end up in a DIFFERENT town. The villagers all provide game info not found anywhere else in the normal towns. If you exit under the overpass to the right, you'll end up in the middle of the ocean, not being able to move in any direction. If you exit to the left, you'll just end up outside Darunia.
** MinusWorld?

** Two words: [[SuperMarioGalaxy Hungry]] [[SuperMarioGalaxy2 Lumas.]]
* ''DonkeyKongCountry 2'' and ''3'' have a "secret" world, that allows access to a better ending and certain items you collect
are focused around gaining access to these levels.

* ''DonkeyKongCountry 2'' and ''3'' have a "secret" world, that allows access to a better ending and certain items you collect are focused around gaining access to these levels.

* ''{{Marathon}} Infinity: Blood Tides of Lh'owon'' has several of theses, which are either alternate endings where the W'rkncacnter destroy the universe, or "co-op carnage break" levels that can (or are supposed to) only be accessed in multiplayer mode. Then there's the three Vidmaster's Challenge levels, found via a secret exit on the final stage.

Many games provide secret levels that [[UnlockableContent aren't necessary to finish the game.]] Sometimes they are based around [[GimmickLevel gimmicks]] or themes that aren't in the "actual" game. Sometimes they are [[BrutalBonusLevel much more difficult than the main game's and are essentially a secret challenge]], or they feel like they could fit right in the game and were seemingly left out of the main game simply because there was no way to fit them into the progression (and making them secret was better than leaving them out or [[DummiedOut dummying them]] ):

* ''TombRaider 3'' has a secret level accessed by finding every (well, technically, all but one, due to an oversight) secret. It appears to have been intended to be a normal level (and showed up in various previews of the game) at first but was cut for some sort of progression reason.
** The ''TombRaider 2'' GaidenGame Golden mask also has a (very wacky) secret level accessed by finding all the secrets in the previous levels.
*** ''TombRaider: Anniversary'' has the "style units" gained after finding most of the secrets. Not really a level as it is just an explorable visual demonstration, but it shows off various experimentations with the art-style of the game and locations.

* Level 4-0 in ''MedalOfHonor: Allied Assault'', accessible only through the console.

* Not sure if this is a SecretLevel or a DummiedOut thing, but in ''Zelda II'', you can go to Darunia and climb on top of houses. If you go to a roof nearest the top of the screen, you can jump off-screen with the JUMP spell, then (while still off-screen) use the FAIRY spell and fly up. You'll get the animation for falling down a hole and end up in a DIFFERENT town. The villagers all provide game info not found anywhere else in the normal towns. If you exit under the overpass to the right, you'll end up in the middle of the ocean, not being able to move in any direction. If you exit to the left, you'll just end up outside Darunia.

* Pretty much every early 2.5D FPS (and 3D, with ''{{Quake}}'') has a secret level at some point or other, whether it's once an episode or just one or two in the whole game. They are usually accessed by using a hidden, secret exit on a level rather than the regular exit.

** ''Crash 3'' does the same once again in accessing hidden levels with alternate routes, but makes you beat time trials to get to them. However, there are still two hidden levels not at all required for 100% completion, but required for the 105% completion.

* The secret Cow Level in ''{{Diablo}}'' 2, which was made after various rumours about one in the original Diablo.

* The Aztec and Egyptian levels in ''{{Goldeneye}}''. The former deals with the Drax Corporation from ''{{Moonraker}}'', and the latter has [[LiveAndLetDie Baron Samedi]], who somehow procured the [[TheManWithTheGoldenGun Golden Gun]] and is taunting MI6 with it (that level doesn't make a whole lot of sense story-wise, come to think about it). The levels carry their own unique challanges: the Drax soldiers have an over-reliance on grenades which sharp-shooting players can turn against them, and the Egyptian tomb has a GuideDangIt method of getting the Golden Gun.

* Not sure if this is a SecretLevel or a DummiedOut thing, but in ''Zelda II'', you can go to Darunia and climb on top of houses. If you go to a roof nearest the top of the screen, you can jump off-screen with the JUMP spell, then (while still off-screen) use the FAIRY spell and fly up. You'll get the animation for falling down a hole and end up in a DIFFERENT town. The villagers all provide game info not found anywhere else in the normal towns. If you exit under the overpass to the right, you'll end up in the middle of the ocean, not being able to move in any direction. If you exit to the left, you'll just end up outside Darunia.
* The N64 game Quest 64 also has a SecretLevel in the [[ShiftingSandLand desert]]. While in a completely unrelated and skippable area, it does have a ton of powerups which are normally hard to find.
* The "Panzerknacker Unleashed" missions in ''MedalOfHonor Underground''. They are based on multiplayer maps from the previous game, and they are [[NintendoHard very, very hard]].

** ''Luigi's Mansion'' has multiple hidden, secret, or otherwise-unneeded rooms inside the game, which are essential for 100% completion and getting all of the ghosts, but is often entirely optional and one may even forget to do them as they play due to the fact they're never mentioned.

* The secret levels in ''PerfectDark'' are markedly different from those in ''Goldeneye'' mentioned above. Instead of brand new levels with no plot significance, they're retreads of previous levels from a different point of view, which reveal different parts of the story. The first one shows how an alien {{Mook}} [[spoiler:kidnapped the CEO of dataDyne (she was later killed aboard the ship) and imploded the building, effectively destroying the company]]. The other two missions let you play as the grey aliens, one where Elvis alerts the Institute of being captured by Area51 and you play through the entire level with diminished health, and the other has you play as a soldier among a platoon who landed on the planet after Joanna dropped the shields. Both missions are ''insanely'' difficult.
* ''Rolling Thunder 3'' for the Genesis has Rounds A-C (one of them being a NostalgiaLevel) that serves to substitute the two vehicle stages (Round 3 and 6), as well as the Hijack stage (Round 9) while keeping all of their current weapons and ammo.

* ''BubbleBobble'', NES (and thus Virtual Console) version has a secret path that the players must take to get the best ending. [[NintendoHard It wasn't there in the arcades]].

* ''{{Tyrian}}'' is absolutely chock-full of secret levels. As a rule, they're accessed by destroying a specific target in a level so that a big glowy sphere appears. When you grab it, you'll move on to the corresponding secret level after finishing the current one. Some of these are tough to get, requiring you to leave certain enemies alone or stay on a certain path. There's even secrets 'within' secret levels, so you can go through a bunch of secret levels in a row before returning to the normal ones.

* ''{{Marathon}} Infinity: Blood Tides of Lh'owon'' has several of theses, which are either alternate endings where the W'rkncacnter destroy the universe, or "co-op carnage break" levels that can (or are supposed to) only be accessed in multiplayer mode. Then there's the three Vidmaster's Challenge levels, found via a secret exit on the final stage.

* ''{{Nitemare 3D}}'' goes straight from level 4 to level 6 if you play it normally. Or, you can simply push a bunch of boxes in front of one of a pair of dumbwaiters (which will otherwise just transport you back and forth) and get in the other to jump to level 5, which is full of gun-wielding human enemies.
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Many games provide secret levels that [[UnlockableContent aren't neccessary to finish the game.]] Sometimes they are based around [[GimmickLevel gimmicks]] or themes that aren't in the "actual" game. Sometimes they are [[BrutalBonusLevel much more difficult than the main game's and are essentially a secret challenge]], or they feel like they could fit right in the game and were seemingly left out of the main game simply because there was no way to fit them into the progression (and making them secret was better than leaving them out or [[DummiedOut dummying them]] ):

** ''Super Mario World 2'' (''Yoshi's island'') had one secret level per world (accessed by 100% completion of the normal levels), generally based around a gimmick or/and much harder than other levels. The advance remake has another secret level per world once the game has been beaten.

* ''RatchetAndClank'' (in 2 and 3) has the Insomniac Museum, where the game's designers stuck a bunch of stuff that "didn't quite make it into the finished game."

* The N64 game [[Quest64 Quest 64]] also has a SecretLevel in the [[ShiftingSandLand desert]]. While in a completely unrelated and skippable area, it does have a ton of powerups which are normally hard to find.

* The N64 game Quest64 also has a SecretLevel in the [[ShiftingSandLand desert]]. While in a completely unrelated and skippable area, it does have a ton of powerups which are normally hard to find.

* The N64 game ''Quest64'' also has a SecretLevel in the [[ShiftingSandLand desert]]. While in a completely unrelated and skippable area, it does have a ton of powerups which are normally hard to find.

* The N64 game ''Holy Magic Century'' also has a SecretLevel in the [[ShiftingSandLand desert]]. While in a completely unrelated and skippable area, it does have a ton of powerups which are normally hard to find.