As they continue their journey through the Johto region, Satoshi and his friends visit Altomare, an island city that hosts an annual racing event called the Pokémon Water Race. While Takeshi and Kasumi are enjoying themselves, strange things seem to be happening to Satoshi—he somehow loses the water race, sees some women attack a girl with their Pokémon, and despite them saving her, the girl later denies ever seeing Satoshi and Pikachu before!

Fortunately for Satoshi, his confusion clears up as he learns that the girl he and Pikachu saved earlier was actually a Pokémon named Latias, who likes to disguise herself as her human friend, Kanon. Latias and another Pokémon, Latios, are known as the Eon Pokémon, as they inhabit and guard Altomare along with a mystical blue sphere called the Soul Dew. An ancient legend of Altomare is highly connected to the Eon Pokémon and the Soul Dew, and is well known among the locals—as well as among Latias' earlier assailants, the thief sisters Zanner and Lyon. As the thieves attempt to capture both the Eon Pokémon and the Soul Dew, Satoshi is forced to act in order to stop them from bringing disaster to Altomare.

[Written by MAL Rewrite]

One summer vacation, Ruka meets two boys, "Umi" and "Sora," whose upbringing contains strange and wonderful secrets. Drawn to their beautiful swimming, almost more like flying, Ruka and the adults who know them are intertwined in a complex mesh... Meanwhile, an unexplained anomaly is occurring all over the world: fish are disappearing. Thus begins a marine adventure of boys and girls to captivate all the senses!

Following a cataclysmic nuclear war, the world teeters on the brink of complete destruction. Civilization is polarized into a degenerate society where opposing packs of marauding scavengers prey on helpless, homeless nomads. For those who are lucky enough to survive the constant brutality and danger, it is a bleak existence. Life an death blur into abstractions. The only hope left for mankind is to find a hero worthy of becoming the next "Fist of the North Star" - an enlightened warrior - who is capable of leading those with the will to survive out of this barrenness into a new world. But in this savage no-man's land of shifting loyalties and power-hungry demi-gods, heroes are in short supply. 

(Source: AniDB)

The land of Altera has observed an uneasy peace for years among Humans, Elves and Evil beasts who are loyal to the legendary Black Dragon. But the Black Dragon begins to stir from its hibernation, sending the Beasts marching across Altera. With a beast conquest perilously close, a small group of Humans and Elves unite to try to find a secret hidden road to the Black Dragon's cave and destroy it. But the fate of all of them may be in the hands of the young warrior Lambert, who must summon the confidence and skill to face the Black Dragon himself just when all may be lost.