Joke Level

A level that feels rather out of place in a video game, in that it goes against the theme of the game and even clashes with the established story and setting. Oftentimes these tend to be Secret Levels, but sometimes, these are a normal part of the game, reachable through normal progression or level selection.

Not to be confused with Gimmick Level.

Beat'Em Up

• Abobo's Big Adventure has a level based on Urban Champion. The champ's attempts to hurt you are ineffective, and he's a total pushover. It ends with a sequence direct from Mortal Kombat (a game that wasn't on the NES).

Fighting Game

• Naruto Shippuden: Ultimate Ninja Storm Generations has The Tale of Killer Bee, which consists of 4 fights with absolutely zero plot justification, sandwiched between Killer Bee rapping about how awesome he is and who he's going to fight next. It certainly fits the "clashing with the overall mood of the game" part of the description. Beware of the surprise SNK Boss at the end though!

First-Person Shooter

• Star Trek Elite Force II had a secret level based on Super Mario Brothers.
• The Secret Level of Batman Doom. See its work page for a more detailed description.
• Wolfenstein 3D has a Secret Level with the layout of a Pac-Man stage called "Wolf Pack", complete with ghosts that chase you, as seen here.
• AS-Outback, an assault mission from Unreal Tournament 2004, is one long parody of the Land Down Under, wherein pissed-off Aussie rednecks, infuriated by the alcohol-free zero beer, go to their local brewery to get back some real beer, fighting against the city slickers who prefer the nasty stuff.

Hack and Slash

• The Secret Cow Level in Diablo II is a secret level with specific requirements to reach it, that clashes a bit with the moody setting of the game. While still dark and realistic looking (by graphical standards of the time), it consists of grasslands containing a massive army of bulls who speak by saying the word "moo" over and over again.
  • And then topped in Diablo III with Whimsyshire. After going through the steps to unlock it, the player is teleported to a mystical land of dancing flowers, smiling clouds, and lots of rainbows. Also doubles as a Take That, Audience! after all the complaints that the early screen shots weren't dark enough.

Platform Game

• NightSky: The vividly coloured "Slightly Nonsense", which is a stark, sunny contrast to the moody sunsets of the preceding worlds, and requires all of the secret stars to access.

Puzzle Game

• Portal 2 has a test chamber which has the word "TEST" written in enormous letters on a wall and is solved as easily as pushing a button. It's designed first to show that Wheatley has no idea how to design a decent test and also as a jab towards the kind of level uncreative users create when they first get their hands on a game's SDK.

Role-Playing Game

• Paper Mario: The Thousand-Year Door has you doing classic levels from Super Mario Bros as Bowser at three points.

Shoot'Em Up

• The secret "Out Of This Dimension" level in Star Fox. The enemies are origami paper airplanes, the background is constantly distorting planets with faces, and the boss is a slot machine.