This year marks the 15th anniversary of Square Enix's video game series "Kingdom Hearts." Originally released in 2002 and created by Tetsuya Nomura, the series is notable for crossing Disney characters and worlds with characters from the "Final Fantasy" video game series. The core games in the series focus on the character Sora as he journeys across different worlds to restore the balance between light and darkness and reunite with his friends.

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Since the release of the original "Kingdom Hearts," there have been seven other games in the series. Additionally, various songs from the soundtrack have been performed live in Japan and America. While "Kingdom Hearts III" has been in development since 2013, the anticipation for the game has been high.  To commemorate the 15th anniversary of "Kingdom Hearts," here are 15 reasons the franchise is so beloved.

15 THE ORIGINAL CHARACTERS

Kingdom Hearts Original Characters

Although the game is comprised of characters from iconic Disney films and "Final Fantasy" games, the heart of this game lies with the original characters created especially for the series. The most important character is Sora, a young boy who lives on Destiny Islands until darkness invades and separates him from his friends Riku and Kairi.  Wielding a giant sword-like key called the Keyblade, he battles dark creatures called Heartless as he travels to various worlds to find his friends.

Besides Sora, his friends Riku and Kairi also have their own roles to play. By the time the player finishes "Kingdom Hearts," you see that all three of them are connected in a larger battle between light and darkness. Other characters that are introduced later in the franchise are also connected to light and darkness, falling in one, the other, or in between. Together, they are a great mix of heroes, villains and anti-heroes that make the franchise engaging.

14 THE DISNEY WORLDS

Beast's Castle Kingdom Hearts Intro

You might enjoy characters like Mickey, Donald, and Goofy, but the "Kingdom Hearts" franchise takes them and makes them even more fun. Imagine fighting side by side with Beast from "Beauty and The Beast" or Mushu from "Mulan" and you'll get an idea of how entertaining the gameplay is. Not only do you get to play with iconic Disney characters and fight Disney villains, but you also get to explore Disney worlds.

By allowing the player to adventure under the sea with Ariel or fly with Peter Pan, the franchise lets Disney fans become part of their favorite films while being part of an even bigger story. At the same time, it also puts an RPG twist on characters like Mickey, Donald, and Goofy by giving them exciting roles in the game. By combining Disney nostalgia with the contemporary style of an RPG, you have Disney magic and adventure at its finest.

13 THE FINAL FANTASY CHARACTERS

Squall and Cloud Strife Kingdom Hearts

Putting characters from the "Final Fantasy" games into the "Kingdom Hearts" games works well for a few reasons. The first reason is that it was a great way to introduce them to newcomers. They are integrated so naturally into the games that you don't have to worry about their back stories if you hadn't played a "Final Fantasy" game before. The other reason that it worked is because of Tetsuya Nomura's experience with the characters, which allowed them to retain their personalities even if the characters didn't play a huge role in the games.

Overall, the most interesting use of these characters involve the worlds known as "Tranverse Town" and "Hollow Bastion." In these worlds, you have popular characters like Yuffie, Leon and Aerith defending the town from Heartless and helping Sora on his journey. They are a kick-butt, quirky bunch of characters to interact with, with their best appearances being in "Kingdom Hearts II."

12 THE MUSIC

Kingdom Hearts Wallpaper

Even if you hate this franchise, it is impossible not to enjoy its gorgeous, epic soundtrack composed by Yoko Shimomura. While some of the musical scores are arranged pieces of music from Disney films, there are also original compositions made for battles, characters, and certain parts of the game. One of the most poignant pieces of music is a simple, yet lovely piano piece known as "Dearly Beloved" and is heard on the main menu for most of the games.

As stated earlier, the music of the franchise is so popular that it has been performed live. This year,  there will be a "Kingdom Hearts" music concert world tour that will commemorate the 15th anniversary of the franchise. In addition to the game's orchestral score, the series is known for its theme songs "Simple and Clean" and "Sanctuary." which are sung by J-Pop artist Utada Hikaru. There is also a grand orchestral theme song that is based on the Japanese Kingdom Hearts' theme song "Hikari."

11 THE STORYLINE

Kingdom Hearts Heroes

 

The simplest way to explain the plot of the franchise is to think of the power of three. "Kingdom Hearts" has three friends who are caught in a war between light and darkness.  Other games including "Kingdom Hearts 358Days/2" and "Kingdom Hearts Birth By Sleep" follow this same formula, with the characters in these games connected to the characters from the first game. The thing that makes them stand out is how their friendships, personal struggles, and heartbreak impact not only each other but the entire battle of good versus evil.

The further you get into the "Kingdom Hearts" franchise, the more intricate and convoluted the storyline gets. It doesn't always make sense and sometimes you have to speculate, but it makes the franchise entertaining. The appeal of the characters at the heart of the storyline has resulted in fans putting their own theories and twists  into videos, fan fiction, and other fan works.

10 CINEMATIC EXPERIENCE

Kingdom Hearts Cut Scene

The opening scenes and the in-game cutscenes make the player feel they are watching a movie rather than playing a game. While the cut-scenes that occur in the game serve to develop the story and characters, the opening scenes either summarize what has happened or foreshadow what will happen. All of these scenes are pre-rendered, with the in-game ones designed to mimic the gameplay. Since this is Square Enix, you can pretty much expect great graphics that will be familiar to anyone who has played a contemporary "Final Fantasy" game.

Between the in-game cut scenes and the opening cutscenes, the opening cutscenes are the ones with the most impressive graphics. Characters and places are so gorgeously detailed that they literally glow sometimes. When put together with the many different versions of "Kingdom Heart's" theme song, you get a viewing experience that is ambient and surreal. Meanwhile, the in-game cutscenes provide a smooth transition between gameplay and story events.

9 FRIENDS ARE LITERALLY YOUR POWER

Kingdom Hearts Mech Fight

One of the most iconic lines from this franchise is, "My friends are my power." Had it not been for the gameplay, this statement would be nothing more than cheesy. Thankfully, this statement is put into action mainly through its three-party character system that allows you to draw power from them to pull off special attacks and activate special powers. The more powerful attack is known as a "Trinity Limit" and is capable of clearing entire fields of enemies when in a tight spot.

While "Trinity Limit" is available in most of the core games, each one is different depending on who is in your party at the time. They can involve anything from exploding spheres of light to devastating slash attacks. When involved with Disney characters besides Donald and Goofy, the attacks are personalized with that character's own unique style. This makes executing Trinity Limits really enjoyable by going beyond the usual hacking and slashing seen in JPRGs.

8 DIVING INTO THE HEART

Dive Into The Heart

In a flash of light, the player finds themselves standing on a beautiful stain-glass pillar lit by white light pouring down from above. This is known as a "Dive Into the Heart," and is considered to be a world within a dream that reflects the heart of the player's character. Despite the dream-like state of this event, what occurs actually affects the real world. Featuring a mysterious voice as your guide and eerie background music, this is one of the most fantastic aspects of the games.

Besides its dreamy aspect and gorgeous stage design, a "Dive Into The Heart" is notable because it usually serves as the tutorial level of the game. You pick an item to fight with and enhance your stats, learn to move around, and fight your first boss with the Keyblade. The trial determines how well you level up for the rest of the game, while the pictures on the stained glass pillars provide a hint about what lies in store for the character.

7 FABULOUS MONSTERS

Kingdom Hearts Monsters

In the franchise, the player fights two different types of monsters known as "Heartless" and "Nobodies."  Heartless are creatures created when someone loses their heart to darkness, while Nobodies are the body and soul that are left behind. An interesting aspect of the Heartless and Nobodies is that they have a variety of appearances. A Heartless could be a small, horned-looking creature or a giant beast, while a Nobody could be a white, splintered upside-down heart or someone with a human appearance.

The concept of "Heartless" and "Nobodies" revolve around the nature of the heart and what happens to it when someone literally loses it. In turn, this is tied to the idea of light and darkness keeping the heart of people and various worlds in balance. In addition to being tied to ideas of good and evil, the monsters are also pretty interesting to look at due to their vibrant and sharp designs.

6 EPIC BOSS FIGHTS

Kingdom Hearts Boss Fights

There is nothing more challenging in a JRPG than a great boss fight and "Kingdom Hearts" is no exception. This franchise has some of the most engaging boss fights ever. You fight enemies that will attack you with weapons or their bodies and unleash devastating moves. Meanwhile, the stage you battle on becomes either an obstacle or a platform to give you a boost when you fight.

On top of all this, Yoko Shimomura's arrangements and original scores get your heart pounding as you try and defeat each boss. In addition to the regular bosses found throughout the core games in the series, there are also secret bosses that you can fight as an extra challenge. All of the boss battles of the franchise add to the magic of the series by being fun and creative in a way that makes you relish each fight until you finally beat the game.

5 SOLO FIGHTS

Kingdom Hearts Solo Fights

Sometimes, a hero must fight alone. Despite using the party system commonly found in JRPGs, there are times when you battle an enemy one-on-one. This occurs when your party can't fight with you in a battle or if you have no party members with you. As a result, it is up to the player to hone their character's unique individual skills rather than just relying on party members to aid you.

Solo fights amp up the stakes in the games and tend to be more dramatic than party fights. At times, it will seem like you're a part of some high fantasy action adventure film due to the fact that you see tight close-ups and the use of slow  motion effects. Depending on whether you're fighting a secret boss or following the story, solo fights will be a little or a lot harder. Either way, they are a refreshing way to play the game.

4 GUMMI SHIP FIGHTS

Gummi Ship Fights on Kingdom Hearts

In some of these games, you travel from world to world via a ship made of blocks called gummies. If you think it's smooth flying, then think again. Between one world and the next are meteors and enemy Heartless ships that you must blast away and navigate around in order to make it to your destination safely. Once you complete each route, the world you are going to is unlocked.

These fights are a throwback to old-school fixed shooter games like "Galaxian" and "Space Invaders." As the series progresses, the stages for these fights improve visually and missions are added to make the experience more enjoyable. As you travel, you gain gummy blocks that you can use to customize your ship and increase your chances of survival. By the time you make it to the next world, it is easy to forget that you weren't originally playing a shooter game.

3 DIFFERENT CHARACTER VIEWPOINTS

Sora Final Form

As stated earlier, Sora is the main protagonist of these games as a whole. However, games that were released after the first "Kingdom Hearts" game have allowed you to play as different characters that are related to Sora's story. For example, in "Kingdom Hearts II," you play as a character named Roxas when you first start the game. Although the player might not know much about these characters, they are still a refreshing way to play each game.

Even though Sora is a lot of fun to play and is  a great protagonist, playing him in every game would've gotten old unless the games followed the footsteps of "Legend of Zelda." By inserting new characters for the player to play as, it adds a new perspective to the storyline and keeps the gameplay from getting stale. Although the gameplay can get repetitive if multiple characters are going through the same worlds, it is worth having a different character to control.

2 UNIQUE WEAPONS

Sora with Keyblade

The Keyblade is the primary weapon of every protagonist in this franchise. It is used to fight Heartless, Nobodies, and other creatures and is used to lock the heart of each world from the darkness. The most basic version of the Keyblade is called the "Kingdom Key," but you can gain other types of Keyblades and enhance them with materials as you get further in the games. Each Keyblade has its own unique attributes that can enhance the stats of your character. Things get even better if your character gains the ability to use more than one.

Meanwhile, the villains of "Kingdom Hearts" have weapons that are just as powerful as the hero's. If they don't have their own Keyblade, then they have weapons that can range from their own fists to magic to chakrams. The wide variety of weapons used by the heroes and the villains make for exciting battles that lets the player strategize about how to defeat them.

1 TIMELESS THEMES

Kingdom Hearts Sora and Mickey Mouse

At the center of "Kingdom Hearts" is a story about how everyone is connected through friendship and love and how light (i.e. good) and darkness (i.e. evil) lies within everyone's heart. There are many quotes in the series that demonstrate these themes, such as the aforementioned "My friends are my power." The most profound lines in the series come when the characters are just thinking aloud in a moment of introspection.

Although "Kingdom Hearts" may come off as cheesy and childish to some, the series represents the struggles we deal with inside ourselves and with each other. It takes the idea of "good vs evil" and shows how complicated everyone's true nature can be. It demonstrates that everyone can fight for the sake of their friends and loved ones, and fight in order to not lose themselves. While "Kingdom Hearts" certainly isn't a perfect video game series, it's themes resonate through its storylines, characters, and battles to create a poignant experience.

What's your favorite thing about the "Kingdom Hearts" video game series? Tell us what you love about the franchise in the comments section!