Recently, I have gotten a review explaining how poor the introduction of my characters were in the story. I am mainly focusing this from the SAO characters point of view, so I didn't give them as much of a description compared to the Kingdom Hearts characters later on in this episode. But I will create a character description of each side. You can still look them up online for further details.
For those who don't know Sword Art Online, here is a well descriptive analysis on the main characters.
Kirito: The main protagonist of the 'Sword Art Online' series. In the real world, his actual name is Kazuto Kirigaya, but Kirito is his in-game name. In this series, he is 17 years old. He lives with his aunt, uncle and cousin, Suguha. He has slightly long, but neat black hair and black eyes, over 5' 6", and he looks older than he appears.
In SAO, his attire is composed of black clothing, including black pants, shirt, boots and fingerless gloves. He also wears the Blackwyrm Coat, a black trench coat, over his attire. He has straps over his shoulders and under them so he can hold the scabbards on his back, where he holds his two swords. His main sword is the Elucidator, a black sword that is incredibly durable and powerful. His second sword is the Dark Repulser, a green-tinted sword that was hand crafted for him in the game. His style of combat is either one-handed sword or two sword style, an ability he can use thanks to his Dual Wield ability in the game, and it comes with a variety of special moves in both styles. In the game, he is lv. 96, and is one of most powerful fighters in the game.
Personality-wise, he is direct, but not very good with words. Due to how he spends most of his time on his computer, he isn't as good around people, so he will go solo quite a lot. However, he is really kind and he cares a lot for others, and is willing to protect them no matter what, especially those closest to him. He is calm, collective, and he rarely shows signs of distress when in combat, though he really gets aggravated in tough battles, even more so to the point where he will go out of control, and will sometimes forget what he has done. Outside of the battlefield, he is more laid back, and is more care-free. His will and determination are basically like most other heroes; incredibly strong and unbreakable.
Asuna: During the SAO arc, Asuna was the main female protagonist, and is Kirito's girlfriend and in-game wife. In real life, her full name is Asuna Yuuki. In this series, she is 18 years old. She has a mother, father, and brother. She has long, brownish-orange hair and hazel eyes. She is slightly shorter than Kirito, a little over 5' 5".
Her SAO attire is color coordinated of white and red. Her garments are a sleeveless uniform with a white cape, a red skirt, detached sleeves with fingerless gloves, white boots with long stockings. She carries her scabbard across her waist. Her weapon is a rapier called Lambent Light. Her style of combat is swift and accurate, thus she wears light armor. She likes fighting in the front lines, but she is a great healer in combat, and has several Rapier Skills under her belt. Outside of combat, she is a master of cooking. She is lv. 94.
Personality-wise, she is kind and helpful, and she doesn't abandon others in trouble. She is proud, and not afraid to get physical when others challenge her authority or only see her as a pretty face. Like Kirito, she can be controlled by her emotions, and will go by instincts. She can't take it when she sees people die, and tends to get a bit emotional. She understands Kirito's personality, though she gets ticked off when he teases others or goes solo. She cares deeply for Kirito, so she always helps him out when needed.
Yui: An AI that took on a personality, and became the in-game daughter to Kirito and Asuna. In this series, Yui takes the appearance of her ALO form, in which she is a Navigation Pixie. She has long black hair and bright black eyes. In her ALO form, she wears a long light pink dress with detached sleeves and pink anklets. Her hair is equiped with a blue flower, and she has clear pink wings. Her attitude is cheery, though she will scold Kirito if he is swayed by other girls. She is fearless and determinate, and due to being a Mental Health Counseling Program, she will eagerly set her 'parents' straight if they feel sad or angered.
Now for those who don't know Kingdom Hearts, here is what you need to know about all the main characters.
Sora: The main protagonist of Kingdom Hearts. He is an upbeat teenager, who gets a bit simple minded at times. However, he is fully aware of the dangers and importance of his quests, and will follow them through to the end. He has a strong sense of justice and an unbreakable heart. He is impulsive at times, and is quick to anger when defending his friends, but is totally sincere about he does or says. His character description is in the story.
Goofy: One of Sora's friends and comrades, and is Captain of the Royal Knights at Disney Castle. He doesn't like using weapons, so instead he fights with a shield. He avoids fighting when possible, prefers peaceful solutions. Though he is simple-minded and clumsy, and constantly the comic relief, he is almost always optimistic and selectively perceptive, able to see things others miss, and is cool when Sora and Donald go ballistic.
Donald Duck: One of Sora's friends and comrades, and is the Royal Magician of Disney Castle. He uses a mage staff in combat. He, like Goofy, is a comic relief character, and does that more than advancing the plot. He is rash and aggressive, but he is always loyal to all of his friends.
DiZ: His real name being Ansem the Wise, He conseals his face in red bandages so as not to be discovered by others. He once studied the hearts and the Heartless, but has stopped his work from fear and disrupting the orders of the world. Ever since his apprentice, Xehanort, betrayed him, Ansem was driven by vengeance, but changed his heart when he saw Riku give up his physical form to help Sora. Now, he is determinate to aiding the heroes in their quest to stop Organization XIII from having their way.
Riku: A childhood friend of Sora's. He is a Keyblade wielder with the power of Darkness, though he will sacrifice himself to save his friends. While trying to help Sora, Riku lost his physical form, and now looks like the Heartless Ansem.
Jiminy Cricket: The small records keeper for Sora, Donald and Goofy, who writes down the story of their journey. He is informative, and aids his friends anyway he can.
Just a note on the a move set told in Ep. 1, the Double Circular, to me, is basically like Link's Sword Spin in Legend of Zelda, only with two blades. The Shooting Star can be best described as a strong, shining pierce with the rapier.