Beat 'em up video games

Beat 'em up is a genre video games where the player progresses through the main story by clearing stages filled with various enemies. It is typically considered a sub-genre of either action games or fighting games.

2D Beat 'em up
Originally, these games were 2D side-scrollers. These games usually required players to beat the enemies on screen before being able to continue scrolling to the next one. Some of theses games had platforming elements. These games were some of the most popular games in the arcades. Many of the beat up games were eventually ported into home consoles such as Mega Drive (Genesis) and SNES with titles as Final Fight, Streets of Rage, and Batman Returns, to name a few. Other popular titles in the arcades included TMNT, The Simpsons, and X-Men.

3D Beat 'em up
With the advent of 3D, beat 'em up games evolved. These games are more combat focused instead of the 2D platforming elements of some 2D beat 'em ups. This type of beat 'em up initially suffered from a bad camera and poor hit detection. Squaresoft (now Square Enix) released the game, The Bouncer, for the PlayStation 2 in 2000, but it had received mixed reviews. The following year, Devil May Cry popularized and set the template for a distinct sub-genre of 3D beat 'em up games: the Hack & Slash.

Levels and enemies
Games usually employ vigilante crime fighting and revenge plots with the action taking place on city streets, though historical and fantasy themed games also exist. Players must walk from one end of the game world to the other, and thus each game level will usually scroll horizontally. Some later beat 'em ups dispense with 2D-based scrolling levels, instead allowing the player to roam around larger 3D environments, though they retain the same simple gameplay and control systems. Throughout the level, players may acquire weapons that they can use as well as power-ups that replenish the player's health.

As players walk through the level, they are stopped by groups of enemies who must be defeated before they can continue. The level ends when all the enemies are defeated. Each level contains many identical groups of enemies, making these games notable for their repetition. In beat 'em up games, players often fight a boss—an enemy much stronger than the other enemies—at the end of each level. In fact, the term "boss" likely originated in beat 'em ups, since this final enemy was literally the captain of the enemies seen earlier in the level.

Multiple characters and players
Beat 'em ups often allow the player to choose between a selection of protagonists—each with their own strengths, weaknesses, and set of moves. Attacks can include rapid combinations of basic attacks (combos) as well as jumping and grappling attacks. Characters often have their own special attacks, which leads to different strategies depending on which character the player selects. The control system is usually simple to learn, comprising as little as two buttons. These buttons can be combined to pull off combos, as well as jumping and grappling attacks. Since the release of Double Dragon, many beat 'em ups have allowed two players to play the game cooperatively—a central aspect to the appeal of these games. Beat 'em ups are more likely to feature cooperative play than other game genres.

Origins: early 1980s to mid-1980s
The first game to feature fist fighting was Sega's boxing game Heavyweight Champ (1976), which was viewed from a side-view perspective like later fighting games. Sega followed it with several more fighting games, including Samurai (1980), a martial arts themed arcade game where the player simultaneously fought multiple opponents in an enclosed area, before proceeding to fight a master samurai in a boss encounter. Bruce Lee (1983) was a martial arts themed single-screen computer platform game that featured fist-fighting, while Chuck Norris Superkicks (1983) was a martial arts themed Atari 2600 action-adventure which used a vertical-scrolling overhead view for exploration and random encounters that switched to a single-screen side view for one-on-one fighting.

However, it was Data East's fighting game Karate Champ (1984) which popularized martial arts themed games. The same year, Irem's Hong Kong cinema inspired Kung-Fu Master (known as Spartan X in Japan) laid the foundations for side-scrolling beat 'em ups with its simple gameplay and multiple enemies. Later that year, Karateka combined the one-on-one fight sequences of Karate Champ with the freedom of movement in Kung-Fu Master, and it successfully experimented with adding plot to its fighting action. It was also among the first beat 'em ups to be successfully ported to home systems. Another title that year, Chinese Hero, experimented with two-player cooperative gameplay and used an overheard view. Nekketsu Kōha Kunio-kun, released in 1986 in Japan, deviated from the martial arts themes of earlier games and introduced street brawling to the genre. The Western adaptation Renegade (released the same year) added an underworld revenge plot that proved more popular with gamers than the principled combat sport of other games. Renegade set the standard for future beat 'em up games as it introduced the ability to move both horizontally and vertically. It also introduced the use of combo attacks; in contast to earlier games, the opponents in Renegade and Double Dragon could take much more punishment, requiring a succession of punches, with the first hit temporarily immobilizing the enemy, making him unable to defend himself against successive punches.

Golden Age: late 1980s to early 1990s
In 1987, the release of Double Dragon ushered in a "Golden Age" for the beat 'em up genre that lasted nearly five years. The game was designed as Technōs Japan's spiritual successor to Renegade, but it took the genre to new heights with its detailed set of martial arts attacks and its outstanding two-player cooperative gameplay; this made it the first co-op beat 'em up, revolutionizing the genre. Double Dragon's success largely resulted in a flood of beat 'em ups that came in the late 1980s, where acclaimed titles such as Golden Axe and Final Fight (both 1989) distinguished themselves from the others. Final Fight was Capcom's intended sequel to Street Fighter (provisionally titled Street Fighter '89), but the company ultimately gave it a new title. In contrast to the simple combo attacks in Renegade and Double Dragon, the combo attacks in Final Fight were much more dynamic. Acclaimed as the best game in the genre, Final Fight spawned two sequels and was later ported to other systems. Final Fight was also the cause for Capcom to be famous and for Technos Japan's bankruptcy. Golden Axe was acclaimed for its visceral hack and slash action and cooperative mode and was influential through its selection of multiple protagonists with distinct fighting styles. It is considered one of the strongest beat 'em up titles for its fantasy elements, distinguishing it from the urban settings seen in other beat 'em ups. Another highly lauded beat 'em up—River City Ransom (1989), named Street Gangs in Europe—featured role-playing game elements with which the player's character could be upgraded, using money stolen from defeated enemies. It was also non-linear, allowing players to explore an open world. In 1990, SNK released beat 'em ups with a first-person perspective: the hack & slash game Crossed Swords, and the fighting & shooting game The Super Spy.

The acclaimed Streets of Rage series was launched in the early 1990s and borrowed heavily from Final Fight. Streets of Rage 2 for Sega's Mega Drive was notable for being one of the first console games to match the acclaim of arcade beat 'em ups. Its level design was praised for taking traditional beat 'em up settings and stringing them together in novel ways, and its success led to it being ported to arcades. Like Final Fight, Streets of Rage 2 has been claimed as "by far the best" scrolling beat 'em up. Another notable beat 'em up was Sega's Arabian Fight (1992), which featured four-player cooperative gameplay and a three-dimensional playfield where players could move between several layers of scrolling backgrounds. The beat 'em up was also a popular genre for video games based on television series and movies, with Teenage Mutant Ninja Turtles a surprise success, and encouraged many more beat 'em up games based on the characters. However, the "Golden Age" of the genre ended in the wake of the success of Capcom's Street Fighter II (1991), which drew gamers back towards one-on-one fighting games, while the subsequent emerging popularity of 3D video games diminished the popularity of 2D-based pugilistic games in general. By the mid-1990s, the genre suffered from a lack of innovation.

Decline: late 1990s to early 2000s
Core Design's Fighting Force (1997) was anticipated to redefine the genre for 32-bit consoles through its use of a 3D environment. However, it was met with a lukewarm reception. Beginning in 2005, the best-selling Japanese series, Yakuza, combined elaborate plots and detailed interactive environments with street brawling action. Despite releases such as these, game reviewers started to pronounce that the genre had died off. By 2002, there were very few new beat 'em ups being released in arcades.

Capcom's Viewtiful Joe (2003) used cel-shaded graphics and innovative gameplay features (such as the protagonist's special powers) to "reinvigorate" its traditional 2D scrolling formula. The Behemoth's Castle Crashers (2008) also featured cartoon graphics, quirky humor, and acclaimed cooperative gameplay. Rockstar Games' The Warriors (based on the 1979 film of the same name), released in 2005, featured large scale brawling in 3D environments interspersed with other activities such as chase sequences. The game also featured a more traditional side-scrolling beat 'em up Armies of the Night as bonus content, which was acclaimed along with the main game and was later released on the PlayStation Portable. Releases such as God Hand in 2006 and MadWorld in 2009 were seen as parodies of violence in popular culture, earning both games praise for not taking themselves as seriously as early beat 'em up games. Classic beat 'em ups have been re-released on services such as the Virtual Console; critics reaffirmed the appeal of some,  while the appeal of others has been deemed to have diminished with time. Although the genre lacks the same presence it did in the late 1980s, some titles such as Viewtiful Joe and God Hand kept the genre alive.

Hack & Slash: early 2000s to present
The Dynasty Warriors series, beginning with Dynasty Warriors 2 in 2000, offered traditional beat 'em up action on large 3D battlefields, displaying dozens of characters on the screen at a time. The series to date spans 14 games (including expansions) which players in the West view as overly similar, although the games' creators claim their large audience in Japan appreciates the subtle differences between the titles. While critics saw Dynasty Warriors 2 as innovative and technically impressive, they held a mixed opinion of later titles. These later games received praise for simple, enjoyable gameplay but were simultaneously derided as overly simplistic and repetitive.

In recent years, the beat 'em up genre has seen a revival in the form of popular 3D Hack & Slash games in the style of Devil May Cry (2001 onwards), including Ninja Gaiden (2004 onwards), God of War (2005 onwards), Heavenly Sword (2006), Afro Samurai (2009), and Bayonetta (2009). Several traditional 2D scrolling beat 'em ups have also been released in recent years, including Scott Pilgrim vs. the World: The Game (2010).