X is a serial in the monthly manga magazine, Asuka published by Kadokawa Shoten. There are currently 11 manga released. Vol. 12 will be released soon. It was then made into a movie in 1996 call "The Destiny War".
Each manga jacket are illustrated with a different character as Tarot Card from one of the Major Arcana. The Tarots that are released now are The Magician, The High Priestess, The Empress. The Emperor, The Hierophant, The Lovers, The Chariot, The Strength, The Hermit, Wheel of Fortune, Justice and The Hang Man. If you want to see what they look like, please go to the gallery.

X takes place in 1999. It is about the battle of destiny, the fate of the earth. Kamui had came back to Tokyo after his mother's death. He met Hinoto, a dreamwalker (a person who can go into people's dreams.) Hinoto have seen the future and the coming of The Dragon of the Earth and Dragon of Heaven. The Dragon of Heaven and Dragon of Earth has seven people to help it fight. They are known as The Seven Seals and the Seven Minors. Kamui had a choice to become one of the Seven Seals or one of the Seven Minions. If Dragon of Heaven wins the battle, earth will be saved. But on the other hand, if Dragon of the Earth wins, Earth will be destroy. At first, Kamui didn't really care about the future much, but when Hinoto told him that the only way to prevent Kotori from dieing was to become a Seal and save Earth. But we then found out that either Kamui becomes a Seal or a Minion, Kotori will still die. The battle between the Dragon of Heaven and Dragon of Earth continues. Earth's destiny is in their hands.