''Audition Online'' (''Audition, Audi'' or ''X-Beat'' in Japan) is a multiplayer online casual rhythm game produced by T3 Entertainment, a Korean company. The game was originally distributed in North America by {{Creator/Nexon}}, but in 2009, announced they would not be renewing their license. Since then, the game has been distributed by Creator/RedBana.

The game has multiple modes. Choreography - C - 4 Key is [[ComplacentGamingSyndrome easily the most popular mode]], in which players must hit a certain number of arrow keys in the correct order and then press the space bar on beat.

Audition Online's North American release features music from well-known artists such as Music/LadyGaga, Music/BoysLikeGirls, {{Music/Kesha}} and {{Music/LMFAO}}.

!! This game provides examples of:
* AIRoulette: The [=NPCs=] have a set difficulty level of sorts, but there will be times when one that is usually easy to beat will get a high Perfect combo and vice-versa.
* AlliterativeName: ''Several'' NPC characters, including (but not limited to):
** Jack Jumpoff
** Travis Trounce
** Felicia Force
** Rachel Raver
** Billy Backstep
** Sara Steppenice
* AndYourRewardIsClothes: Somewhat averted, as some rooms (as well as licensing matches) require the in game currency, Beats, but otherwise, clothes are the only thing you're earning them for.
* AwesomenessMeter: The ranking for timing goes Miss, Bad, Cool, Great and Perfect. Since Perfects are had to achieve and much less common than Greats, they are worth much more points, especially if you can make a combo of them.
** Also played with in Insane mode.
* BlindIdiotTranslation: Some of the lines in Story Mode look like they were run through Google Translate and then slapped into the game. Some of this has been fixed, but it's still quite noticeable.
* TheChosenOne: Your character in Story Mode.
* DoesNotLikeMen: Perna/Nana in Story Mode. The narration even describes her as "the [[BlindIdiotTranslation despiser]] of men."
* DoWellButNotPerfect: Mission 4 in Episode 1 of Story Mode requires you to get exactly second place.
* ForcedTutorial: At the beginning.
* JustLikeRobinHood: The Masked Dancer/Diego in Story Mode. Your character even calls him "Diego Hood" when you first meet.
* LethalChef: David.
* TheMole: [[spoiler:Jack/Scotch]] is revealed to be one in Episode 2.
* PurpleEyes: An option in the item shop. [=NPCs=] Bobby, Felicia Force, and Perna/Nana all have them, as well.
* RaceLift: Due to a bug, David's model and portrait [[http://i1214.photobucket.com/albums/cc487/iMochiix3/2012_4_5_33244.jpg don't match]].
* TrappedInAnotherWorld: Your character in Story Mode.
* ZettaiRyouiki: Tiahna's a Grade B.