Osu!
osu! is a free-to-play rhythm game primarily developed, published, and created by Dean "peppy" Herbert. Inspired by iNiS' rhythm game Ouendan, it was written in C# on the .NET framework, and was released for Microsoft Windows on 16 September 2007. The game has throughout the years been ported to macOS, Linux, Android and iOS. 

Asides from Osu! Tatakae! Ouendan, the game has been inspired by titles such as Taiko no Tatsujin, Beatmania IIDX, Elite Beat Agents, O2Jam, StepMania and DJMax. The game is heavily community-oriented, with all beatmaps and playable songs being community-made through the in-game map editor. Four different game modes exist, offering various ways to play a beatmap, which can also be combined with addable modifiers, increasing or decreasing the difficulty. 

The original osu!standard mode remains the most popular to date and as of 2021, the game has over 15,200,000 registered users.

Gameplay and features
There are four official game modes: "osu!" (Called "osu!standard", "osu!taiko", "osu!catch", and "osu!mania"). Each mode offers a variety of beatmaps, playable songs ranging from "TV sized" anime openings to "marathons" surpassing 7 minutes. In osu!standard, beatmaps consist of three items – hit circles, sliders, and spinners. These items are collectively known as "hit objects" or "Circles" and are arranged in different positions on the screen at different points of time during a song. Taiko beatmaps have drumbeats and spinners. Catch beatmaps have fruits and spinners, which are arranged in a horizontally falling manner. Mania beatmaps consist of keys (depicted as a small bar) and holds. The beatmap is then played with accompanying music, simulating a sense of rhythm as the player interacts with the objects to the beat of the music. Each beatmap is accompanied by music and a background. The game can be played using various peripherals: the most common setup is a graphics tablet or computer mouse to control cursor movement, paired with a keyboard or a mini keyboard with only two keys.

The game offers a buyable service called osu!supporter, which grants many extra features to the user. Players are able to download beatmaps directly from inside the game, without the lengthy process of using browsers through a service called osu!direct. Features include a heart icon beside the username on the official osu! website, additional pending beatmap slots, faster download speeds, access to multiplayer on cutting edge builds, friend and country-specific leaderboards, one free username change, more in-game customization, a yellow username in the in-game chat, and more customization on one's user page (the "me" tab). osu!supporter does not affect the ranking system, or provide any in-game advantage. osu!supporter is not a recurring service.

Community and competitive play

Community events 
osu! also features different events, such as fanart and beatmapping contests. Unofficial events and conventions are also being held. The biggest unofficial event held in the community is "cavoe's osu! event" (Usually referred to as "osu! event" or "COE"), held at The Brabanthallen in 's Hertogenbosch, The Netherlands. The event has been arranged three times since 2017 yearly. However, due to the COVID-19 pandemic, COE 2020 was cancelled. There were also official stands at TwitchCon and Anime Expo.

Tournaments 
osu! contains three main facets of competition between players. In multiplayer lobbies, up to 16 users play a map simultaneously. On individual maps, players compete for highscores on global leaderboards or against highscores set by themselves and friends. Players also compete with their ranks, which are calculated by accumulating "performance points" (pp). pp is based on a map's difficulty and the player's performance on it. In July 2019, a player, Vaxei, exceeded 1,000pp for the first time, followed by another player, idke, less than twenty-four hours later.

Since 2011, there have been nine annual "osu! World Cups" (usually abbreviated as "OWC"), one for each game mode (osu!mania having two for four key and seven key). Teams for World Cups are country-based, with up to eight players per team. There are also many different community-hosted tournaments, differing in rank range, types of maps played, and how the teams are composed. Winners of tournaments typically receive prizes such as cash, merchandise, profile badges and/or osu!supporter subscriptions.

Adaptations

osu!stream 
In 2011, osu!stream was released as an adaptation of osu! for iOS devices running iOS 6 and later, also developed by Dean Herbert. The main difference between osu! and osu!stream is that osu!stream beatmaps are not user-created and are instead made by the developers of osu!stream. The version also includes some new gameplay elements.

On 26 February 2020, Herbert announced that he released the source code and plans to halt development of the game, releasing one final update that made all the levels free to download.

osu!lazer 

osu!lazer is a free and open source remake of the original game client under heavy development. It was originally projected for the stable version to come out in 2017. However, , not all features were working.

The development of osu!lazer started in 2015 and development versions of osu!lazer are currently available for testing on Microsoft Windows, MacOS, Linux, Android, and iOS. osu!lazer is written entirely in .NET (formerly .NET Core).

Related projects

osu!framework 
osu!framework is an open source game framework developed with osu!lazer in mind. The goal of osu!framework development is to create a versatile and accessible game framework that goes further than most, providing things out-of-the-box such as graphics, advanced input processing, and text rendering.

McOsu 
McOsu is an open source game client designed to play osu!standard beatmaps, available on Windows, Linux, MacOS, and the Nintendo Switch.

The focus of McOsu is to provide an unofficial osu! client for practice, featuring tools that allow players to retry specific parts of beatmaps. McOsu also offers virtual reality support. This game client does not allow players to gain "performance points" or to increase their official ranking.

Reception 
Jeuxvideo.com reviewed osu! favorably with 18/20 points in 2015. In 2010, MMOGames.com reviewer Daniel Ball said that while the game was very similar to Elite Beat Agents, it was differentiated by its community's large library of high-quality community made content and customization. osu! has been used and recommended by esports players such as Ninja and EFFECT, as a way to warm-up and practice their aim.

Notes

References

External links
 
 osu!lazer GitHub page 
 
 Official osu! wiki

2007 video games
IOS games
MacOS games
Music video games
Rhythm games
Open-source video games
Creative Commons-licensed video games
Video games developed in Australia
Windows games
Windows Phone games
Software using the MIT license