The year is Post Disaster 323. More than 300 years after a great war between Earth and Mars known as the "Calamity War", Mars has been successfully terraformed and colonized by humans. However even with the technological advancements, the humans on Mars crave freedom against the government of Earth and seek to improve their livelihoods. Furthermore, while most of Mars' nations have received autonomy, the planet is virtually dependent on Earth for economic development. A young orphan named Mikazuki Augus is part of a group of children who work for the civilian security company Chryse Guard Security, entrusted with the safety of the Martian Princess Kudelia Aina Bernstein, who has plans for her nation of Chryse to secure independence from Earth. One day, the group was attacked by the Earth Military organization Gjallarhorn, which aims to stop the Martian independence movement. During the attack, the leader of the children and the Third Army Division within CGS, Orga Itsuka, decides to rebel against the adults and higher-ups who had escaped and left the children and foot-soldiers to remain and fight as decoys. Augus must now choose to either follow his friends, or his mission as he stumbles into the legendary mobile suit: the Gundam Barbatos.

As the world is in the middle of an industrial revolution, a monster appears that cannot be defeated unless its heart, which is protected by a layer of iron, is pierced. By infecting humans with its bite, the monster can create aggressive and undead creatures known as Kabane. On the island Hinomoto, located in the far east, people have built stations to shelter themselves from these creatures. People access the station, as well as transport wares between them, with the help of a locomotive running on steam, called Hayajiro. Ikoma, a boy who lives in the Aragane station and helps to build Hayajiro, creates his own weapon called Tsuranukizutsu in order to defeat the creatures. One day, as he waits for an opportunity to use his weapon, he meets a girl named Mumei, who is excused from the mandatory Kabane inspection. During the night, Ikuma meets Mumei again as he sees Hayajiro going out of control. The staff on the locomotive has turned into the creatures. The station, now under attack by Kabane, is the opportunity Ikoma has been looking for.

As a magic weilder, young archivist Chakuro knows his life will be short, but everything changes when a mysterious girl from the outside arrives on his island.

A ten year old boy wants to become the best duelist, like his father in the duel masters world.

As the world is in the middle of an industrial revolution, a monster appears that cannot be defeated unless its heart, which is protected by a layer of iron, is pierced. By infecting humans with its bite, the monster can create aggressive and undead creatures known as Kabane. On the island Hinomoto, located in the far east, people have built stations to shelter themselves from these creatures. People access the station, as well as transport wares between them, with the help of a locomotive running on steam, called Hayajiro. Ikoma, a boy who lives in the Aragane station and helps to build Hayajiro, creates his own weapon called Tsuranukizutsu in order to defeat the creatures. One day, as he waits for an opportunity to use his weapon, he meets a girl named Mumei, who is excused from the mandatory Kabane inspection. During the night, Ikuma meets Mumei again as he sees Hayajiro going out of control. The staff on the locomotive has turned into the creatures. The station, now under attack by Kabane, is the opportunity Ikoma has been looking for.