The games attempt to mimic many features of playing a real guitar, including the use of fast-fingering hammer-ons and pull-offs and the use of the whammy bar to alter the pitch of notes.

RedOctane was bought by Activision in June — who spent US$100 million to acquire the Guitar Hero franchise[3] — while it was announced in October that Harmonix would be purchased by MTV Games.

It expanded upon the gameplay popularized by the Guitar Hero series by adding drum and microphone instruments, allowing players to simulate playing songs as bands.

[14] In November 2010, Activision also closed Budcat Creations, the arm of the publisher that was primarily responsible for porting the Guitar Hero games to the PlayStation 2.

[23] Another source close to Vicarious Visions had reported to Kotaku that while Guitar Hero 7 was in development under an Activision studio, the game was considered a "disaster".

[24] Though the team had a two-year development cycle, it was closed down after Activision president Eric Hirshber had seen the current state of the project at the one-year point.

[25] No further downloadable content for either Guitar Hero or DJ Hero was made after February 2011,[26] though Activision committed to releasing content that was already in development by that time due to fan response;[27] later, in a move described by Game Informer as "the final nail in [the series'] coffins",[28] Activision announced it would discontinue all DLC sales for the series without revoking access to tracks already bought as of March 31, 2014.

The career mode used full-motion video taken from the perspective of a lead guitarist underneath the note highway, to create an immersive experience to the player.

[48] A larger number of real-world musicians appear as playable characters, including Jimi Hendrix, Billy Corgan, Hayley Williams, Zakk Wylde, Ted Nugent, Travis Barker, Sting, and Ozzy Osbourne.

Artists including Johnny Cash, Matt Bellamy, Carlos Santana, Kurt Cobain and Shirley Manson appear as playable characters in the game.

It is the last game in the series developed by Neversoft's Guitar Hero division prior to its dissolution, with Vicarious Visions assisting on the Wii version with added Nintendo DS functionality.

The game was criticized for its small selection of songs, and in one case compared unfavorably to Lou Reed's album Metal Machine Music for allegedly being a mere contractual obligation project.

[73] A third title in the series, Guitar Hero On Tour: Modern Hits, was announced following various rumors of its existence,[74][75] and was released in June 2009, featuring songs recorded since the year 2000.

[92] Pi Studios, which had previously helped to port Rock Band to the Wii, had started work on the karaoke title Sing Hero before Activision cancelled its development.

[95] It was later revealed that Mustaine was working with Activision for music in Guitar Hero: Warriors of Rock, including an original track ("Sudden Death") recorded specifically for the game.

Success or failure will cause the on-screen Rock Meter to change, gauging the current health of the performance (denoted by red, yellow, and green sections).

Also, regardless of whether sustains are hit early or late, if the fret is held for the full duration of the hold, the game will always award the same amount of score increase for the note.

[100] While the song is playing, the background visuals feature the players' chosen avatar, along with the rest of the band performing in one of several real and fictional venues.

Guitar Hero II added special lighting and other stage effects that were synchronized to the music to provide a more complete concert experience.

Guitar Hero III introduced Boss Battles, in which two players face off against each other, attempt to collect "distractions" to throw at their opponent, trying to make them fail.

However, in late 2009, both Courtney Love and the members of No Doubt sought legal action against Activision for the misuse of their in-game characters singing or performing songs by other artists, which the musicians believe fell outside of their contract.

The ability for the players to create their own avatars was added in Guitar Hero World Tour, and was based on Neversoft's existing character creation tools from the Tony Hawk series.

Most of the games in the Guitar Hero series feature a selection of songs ranging from the 1960s to present day rock music from both highly successful artists and bands and independent groups.

Many of the Guitar Hero games developed for the recent generation of consoles (Xbox 360, PlayStation 3, and Wii) support downloadable content, allowing players to purchase new songs to play in the respective titles.

Dusty Welch of RedOctane stated, "Where there's music, there's Guitar Hero, and with iTunes, we are able to provide fans with a central location for downloading their favorite rock anthems.

[163][166] Guitar Hero III, according to Activision, was the first single video game to sell more than US$1 billion at retail, with nearly 3.5 million copies sold during the first seven months of 2008.

[210] Jesse Divnich of Electronic Entertainment and Design Research commented that, much like Dance Dance Revolution, Guitar Hero and other music games explosively grew initially due to significant new features from other games but have become stagnant due to focusing on content over features, and suggested that for the genre to continue to grow, they must look to incremental changes as done with the first-person shooter genre.

[215] Critics argued that Guitar Hero should have been doing the same, either through releasing expansions that could be incorporated into the main games of the series, or by issuing the songs as downloadable content.

[103] The large number of Guitar Hero and Rock Band titles on the market is considered to be partially responsible for the sharp decline of music game sales in the latter half of 2009, along with the effects of the late-2000s recession.

[231] Analysts predicted that the market would evolve to support a smaller number of titles each year, averaging at a "healthy" value in the range of $500–600 million in revenues annually.