Earlier this month, news broke that Legendary Entertainment was quietly developing two live-action films based on Nintendo's first two Pokemon video games, Pokemon Red and Blue, with one serving as a direct adaptation of the events in the 1996 Game Boy titles. Selling over 31 million copies worldwide upon its initial release, the companion games launched a bonafide multimedia phenomena, spawning all sorts of merchandising, a popular trading card game, spinoff video game titles and an anime series that led to its own line of animated feature films.

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Created by game designer Satoshi Tajiri, who drew from his childhood hobby of insect collecting, the games introduced the fictional world of Kanto, populated with 151 different adorable creatures that could be caught and trained to battle others in competitive fights. In a formula that would be replicated repeatedly over the following 20 years, the two games split the total number of Pokemon between them, allowing players to trade creatures not found in their game as part of their quest to become the very best and defeat their rival.

blastoise charizard red blue pokemon

Spending over $50 million to market the new video game franchise, Nintendo had the game include both cute and beefed-up creatures to appeal to wider audiences. Providing an accessible, yet varied RPG gameplay, the game was an overnight success. A trading card game originally published by Wizards of the Coast had schoolchildren trading their favorite Pokemon during lunch and recess while several spinoff video games, including Pokemon Snap!, Pokemon Stadium and Pokemon Pinball, only accentuated its success. Meanwhile, Pikachu and Jigglypuff would both have prominent appearances in the original Super Smash Bros. on the Nintendo 64.

As with many popular video games targeting younger audiences at the time, the first two games would inspire an anime series, Pokemon: Indigo League, in 1997. Naming the usual Pokemon trainer as Ash Ketchum, the series followed Ash as he traveled the world with his trusty Pokemon Pikachu and continued to catch and train Pokemon with his friends to defeat his rival, Gary. The series would similarly prove popular with audiences and led to animated movies featuring the series' cast, starting with Pokemon: The First Movie, which would go on to earn $163.6 million at the worldwide box office after its release in 1998.

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By 1999, Nintendo sought to continue to expand the franchise by releasing the sequel games Pokemon Gold and Silver, introducing 100 brand new Pokemon and new regions to the world. While the sales did not ultimately match those of Red and Blue, the video game series continued to thrive and grow, proving that the success of the original two games was no one-time fluke as new titles and spinoffs continue to solidify the franchise as one of Nintendo's most popular properties.

Despite the brand continuing to grow and move into the future, Nintendo has regularly revisited the original games, extending its success and reconnecting players with the nostalgic fun the first two installments provided. In 2004, Nintendo released Pokemon FireRed and LeafGreen, enhanced remakes of the original games for the Game Boy Advance. The remake titles were a surprise success and sold over 11 million copies worldwide, leading Nintendo to realize how enduring the appeal of the original generation of Pokemon was with fans.

By 2016, Nintendo began to branch into more into conventional mobile games rather than exclusively release titles for its handheld consoles. The most popular of all of Nintendo's mobile titles was 2016's Pokemon Go, which prominently positioned the first generation of Pokemon. The freemium game combined augmented reality technology that allowed players to "see" Pokemon in the real world and collect them. The game saw over 800 million worldwide downloads in the two years since its launch and earned over $3 billion in user purchases; more than that, it catapulted the franchise back into the mainstream.

The renewed interest in Pokemon has led to a renaissance of sorts for the video game franchise in the United States. A new set of enhanced remakes for the original games, Pokemon: Let's Go, Pikachu! and Let's Go, Eevee! were released last year for the Nintendo Switch, incorporating elements of Pokemon Go into the gameplay. The first live-action Pokemon movie, Detective Pikachu, is scheduled to be released in theaters everywhere this May with international superstar Ryan Reynolds voicing the eponymous pocket monster. Advance buzz on the upcoming film has been so strong, with Warner Bros. and Legendary Entertainment already commissioning a sequel to the film with the planned Red and Blue adaptation reportedly set in the same shared cinematic universe.

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Nearly 20 years since its original debut, Pokemon remains one of the biggest successes in Nintendo's extensive library of video game properties. Reinvigorated by its arrival in mobile gaming, the franchise does not appear to be losing relevance and momentum as it has spawned a new wave of merchandising and tie-in multimedia to position it to wider audiences throughout the year.

All borne from childhood memories of insect collecting, Pokemon Red and Blue started a global pop culture revolution that has wowed players young and old for decades, and inspired countless knock-offs including Yu-Gi-Oh and Digimon. None, however, have enjoyed the staying power of the original, which remains the most beloved generation in a franchise populated by memorably adorable monsters. With new games and movies on the way, 2019 is sure to continue the Nintendo property's ubiquitous success as the franchise moves into the future.

Directed by Rob Letterman, Detective Pikachu stars Justice Smith, Kathryn Newton, Ken Watanabe and the voice of Ryan Reynolds. The film opens in theaters on May 10.