In only about 50 years, video games have morphed from a small niche hobby industry to one of the most lucrative entertainment businesses in the world. While many smaller games, especially early in the medium's history, have been developed in mere months, most modern games take at least two or three years to create.
Unfortunately for fans awaiting new games and for developers stuck on the same project for years on end, some games get stuck in developmental purgatory. While many problematic games will get canceled to redivert resources to more promising work, others allow developers to finish what they started.
10 Darkfall Online (8 years)
Because of the amount of content needed to sustain an MMO, any game planning to host a massive multiplayer gaming experience will probably take several years longer than most to develop. Even so, Darkfall Online took an insane amount of time to release.
For some reason, even with such an elongated developmental cycle, Darkfall Online failed to deliver on many of their promises at launch. Despite a buggy release in 2009, the MMO went on to be a moderately popular title among fans of the genre.
9 Spore (8 years)
If you have ever wanted to control the entire evolutionary and industrial process for a species, 2008's Spore can scratch that itch. While many games will give you total control over entire civilizations, such as Sims, Spore gave nearly unparalleled control to players.
While Spore, like practically all the games on this list, did not release when its developers originally planned, the game did release to strong reviews. While it boasts a Metacritic score of 84 from critics, fans on the review aggregation gave it a disappointing score of 5.4 because of a disdain for dumbed-down mechanics and restrictive DRM settings.
8 The Last Guardian (9 years)
Shortly after the launch of the PS3 console, development on The Last Guardian began. While Sony showed off the title as early as 2009, the game was delayed so much that the game did not release until midway through the Ps4's lifecycle in 2016.
Thankfully for the studio, the action adventure game was released to critical acclaim. Metacritic lists an impressive thirteen critic reviews that gave the game 100, a testament to the artistic merit of the long-awaited title. Even fans on Metacritic, who are notorious for providing low scores, were generous enough to give the game high marks of 8.0 on the site.
7 Too Human (9 years)
While other games have been announced for a system before withdrawing support, such as Halo: Combat Evolved forsaking Mac or Mighty No. 9 removing handheld devices from its platforms, few games have experienced the roller coaster that Too Human saw.
Although Too Human originally set its sights on the original PlayStation console, its developer soon partnered with Nintendo. The game remained in developmental hell for several years until Silicon Knights began collaborating with Microsoft. The Xbox 360 exclusive was panned by critics, had mediocre sales, and the intended sequels were never developed.
6 Team Fortress 2 (9 years)
After the popularity of the fan made Quake mod, Team Fortress, Valve brought the mods' creators onto their team to begin development on a full-fledged title. Team Fortress 2 was publicly shown as early as 1999, only a year after the developer duo joined Valve.
After a delay in 2000, however, little was mentioned until another showing in 2006; the two leads worked on other projects, slowing the release of the long-awaited game. When TF2 eventually left the vaporware stage at release in 2007, the title proved to have staying power; thirteen years later, Valve's hit remains one of the most popular titles on Steam.
5 Final Fantasy XV (10 years)
The Final Fantasy series has had as much staying power within the gaming world as just about any other franchise, remaining a fixture since the initial title in 1987. With countless spinoffs in addition to the fifteen main titles, it would take countless hours to complete the whole series.
For Final Fantasy XV, development started in 2006 as Final Fantasy Versus XIII. The game was delayed repeatedly until its target platforms shifted to the PS4 and Xbox One. Eventually, the title morphed into Final Fantasy XV as the project was restarted. Surprisingly, the ten years needed for this game won't be the longest in the series; the remake of FF7 debuted as tech demo in 2005 and will not begin its episodic release until later this year.
4 Prey (11 years)
The survival horror title Prey, debuting in 2006, was subject to countless problems, delays, and revivals after beginning development in 1995. With problems partially due to the feature of portals used for traversal of the game world, the game eventually released after suffering eleven years of struggles.
In addition to its long developmental span and some innovative first-person shooter mechanics, Prey also is notable for featuring a Native American protagonist. While there were concerns about stereotypical depictions leading up to release, the game was praised for the representation; Tommy Tawodi is widely considered one of the best Native American protagonists in video games.
3 Diablo III (11 years)
The popular RPG Diablo III began development in 2001 under the Blizzard North studio. After the success of the franchise's first two games, Blizzard had high expectations for the next sequel. Unfortunately, the game was progressing so badly that Blizzard decided to close the studio.
Despite some troubles at launch, the 2012 release found wide praise from reviewers. With eventual ports to the PS3, PS4, Xbox 360, Xbox One, and Switch, Diablo III has had one of the highest ratings--and largest sales--of any game on this list.
2 Mother 3 (12 years)
The sequel to the Japan-only release Mother and the worldwide title Mother 2 (better known to international audiences as EarthBound), Mother 3 has only ever been officially available in Japan. While developers initially hoped to release the title for the Super Famicom, technical limitations moved the goal towards the Nintendo 64, the Japan only 64DD peripheral, and to the Gamecube.
After years of trouble, the developers shifted their attention to releasing for the Game Boy Advance, where the game would eventually release in 2006 after the team decided to shift back to 2D graphics.
1 Duke Nukem Forever (15 years)
The saga of the 90s action hero has three claims to fame. Not only is Duke Nukem Forever the game with the longest developmental time, but it also is the most aptly named. The game that took a decade and a half to finally release would include the word "forever" in its title.
Perhaps the most unfortunate of its "accolades" is that Duke Nukem Forever spent so long on a title that was rated so poorly. The Metacritic score for the PC is a mere 54. Unfortunately, the PS3 and Xbox 360 scored even more pathetically.