There are myriad reasons for this shift - shrunken development times, hardware limitations - but we can dismiss them all by looking at other top-tier games. Boom Blox, LittleBigPlanet, most EA Sports team games and more than a few first-party Wii games carry the four-player torch with little issue (as does Rock Band, though, to be fair, its price premium puts it on a different level). Halo 3, Mario Kart Wii and Call of Duty 4 go a step beyond, proving that modern consoles can run high-octane four-player action via split screen and not slow to a crawl.
But after taking one step forward, Call of Duty 4 took two - or perhaps four - steps back. CoD4 is renowned for its dangling-carrot reward system: Play more online games, get more weapons and items. Unfortunately, only one player at a time can play online, and with maps clearly designed for 16 players, four-player deathmatches feel rather empty. These kinds of design decision encourage groups of friends to play separately from home rather than in each other's company.
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Originally, getting two players into a videogame, let alone four, wasn't a fundamental goal of the medium. That seems illogical - uh, Pong? - but the earliest arcade developers usually favored impossible, quarter-munching challenges for one. Home consoles and computers were the proving grounds for early multiplayer gaming: The short bursts of two-player action in Atari's Combat were too simplistic for the flashy arcades, while thoughtful strategy games like M.U.L.E. would have been difficult to price on a per-quarter basis.
It wasn't until 1983 that a little-known Atari 800 game, Dandy, teased the idea of simultaneous four-player action. Unsurprisingly, this dungeon crawler drew inspiration from the world's first great multiplayer game, Dungeons & Dragons. (Dandy, "DandD," get it?) Atari may have ripped off Dandy's creator when it introduced Gauntlet to arcades, but while the fantasy archetypes were similar, the latter's inclusion of four joysticks in one cabinet made it distinct enough to start an arcade revolution.
As game tech advanced, the arcade remained the ideal destination for no-frills four-player action. Licensed fare from Konami dominated the four-player scene at the turn of the '90s - Ninja Turtles most famously - and Gauntlet's team play set a standard, as arcade multiplayer games were typically co-op affairs. Before Street Fighter II came along, your computer opponents were the source of challenge, not your friends.
Home console games added a few more competitive options, but they didn't matter: Most people couldn't play them. Four-player games required adapters like the Four Score and Super Multitap, which were pricey niche add-ons. Rather than waste resources on multiplayer-focused games, designers typically took the easy route and added extra players to standard sports games or ported four-player arcade hits like NBA Jam that already had a following.
