Touhou Xenoglossia Z: Introduction
108 years ago, the moon was completely destroyed. The devastation of its lack of gravitational pull has had a major effect on the planet's tides and overall ecosystem stability. Making things worse were the fragments of "Lost Artemis" that frequently fell to Earth, bringing yet more destruction in their wake. In order to combat this, the organization Mondenkind, had deployed five iDols built around very powerful harmonically tuned cores found in the wake of the moon's destruction. Piloting these giant robot iDols were iDOLMsters, who must be female in order for the iDols to allow control. These iDols were then deployed during meteor showers and used to destroy large asteroids with high powered sonic shockwaves emitted via a nicely delivered punch. Making Mondenkind's trouble worse was the organization Turiavita, which sought to steal away all the iDols from Mondenkind and its iDOLMsters and allow the destruction of humanity to occur so its own touted superior genetically engineered race of iDol/Human hybrid called the Mischlings could take over in its place. Much of the conflict was about the battle between Mondenkind and Turiavita for control of the iDols as well as the shifting bonds and rivalries between the iDOLMsters themselves.
Eventually, the conflict between Mondenkind and Turiavita resulted in the emergence of a super-powerful force known as Auryn, which almost resulted in the complete destruction of the earth. The iDols Imber, Nebula, and Hiems and their iDOLMsters fought against this force and won, but at the cost of the iDols themselves. With the entire planet saved, life started to go on. Several months after the "Auryn Incident", new asteroid belts have appeared around the earth, and without iDols to confront them, Mondenkind, how having started a space program, has set up massive arrays of laser satellites, missile systems, space cannons, and defense platforms around the earth to eliminate any threats that may come from above. The Vulturius cannon has also become a part of the Mondenkind cosmic defense system and they are also looking into making a man-made moon using Epimetheus (man-made iDol cores) technology.
It is now Haruka Amami's 17th birthday, and her friends and allies from when she had worked at Mondenkind, Iori Minase, Yukiho Hagiwara, Makoto Kikuchi, Ritsuko Akizuki, and the twins Ami and Mami Futami, have all gathered at the dorm where Haruka lived at during her time as an iDOLMster to celebrate the occasion. As it's to be a surprise party, Haruka's childhood friend, Yayoi Takatsuki, has decided to take her to the studio where the two work as typical idols until everything for the party is ready. Meanwhile, in a distant place known as Gensokyo, a stadium has been built for a major event known as the Gensokyo Danmaku Tournament. A bunch of females from all over, only a few of them actually human, have decided to take part in this event. In the first round, Reimu Hakurei, the well-known shrine maiden of the Hakurei shrine, is going up against Aya Shameimaru, a tengu reporter and photographer. The battle takes to the skies and in the end, Reimu ends up victorious. Next up is Marisa Kirisame, a western-style witch against Cirno, a childish ice fairy who constantly boasts about being the strongest, but is actually not very bright. The battle is short as Marisa comes out on top.
Meanwhile, out in space, five objects can be seen cruising towards Earth. These objects then suddenly vanish. Back on Earth, we can see that Haruka, Iori, Makoto, and Yukiho still carry around the keys they used to pilot their respective iDols, although they are now powerless. However, these keys suddenly start glowing. Back in Gensokyo, the Danmaku Tournament continues as the next round commences. Here, we see Sanae Kochiya, the shrine maiden of the Moriya Shrine, and a young woman from back outside Gensokyo, face off against Sakuya Izayoi, the chief maid of the Scarlet Mansion. While Sakuya seems to have the upper hand with her time-manipulating abilities, using attacks she learned from her two superiors, Kanako Yasaka and Suwako Moriya, Sanae manages to come out on top. However, in the next round, Sanae is soundly defeated by Marisa. Reimu's next foe happens to be Reisen Udongein Inaba, a humanoid rabbit from a remnant of the moon. Managing to overcome Reisen's "Lunatic Red Eyes", Reimu wins this round.
The final round of the tournament pits Reimu and Marisa against each other. The battle goes on for what seems like forever as Ying-Yang Orbs and Master Sparks fill the arena. Meanwhile, we see the same five objects from earlier enter Gensokyo along with countless thousands of strange crystal shards. Upon closer inspection, the five objects are the iDol cores; Imber, Nebula, Nubilum, Hiems, and Tempestas. The cores crash into Gensokyo and at the same time back on Earth, each of the iDol keys let out a bright flash that envelops those holding them. When it comes to Haruka, Yayoi is also enveloped in the light. Back in Gensokyo, we see Meira, a female samurai that took on Reimu several years ago training somewhere near the Forest of Magic. Meira sees a woman with blue hair standing in front of her who promptly asks where Imber is. Meira, somehow terrified by the woman, says that she doesn't know what the woman is talking about. Suddenly, we see a light glow in front of Meira as the woman decides that Meira is of no use to her. As we head out to outside of the forest, we see a large flash as Meira lets out a loud scream.
Back at the Gensokyo Danmaku Tournament, Reimu is charging up a Ying-Yang Orb while Marisa is charging up a Master Spark when suddenly a bright flash appears in between of them. From the flash we see Haruka and Yayoi emerge. Not knowing of these two girls, Reimu accuses them of being youkais and she and Marisa decide to deal with them. However, Haruka unintentionally puts her hand over a crystal shard and suddenly, another flash occurs as armor similar to Imber appears around Haruka. As Reimu and Marisa prepare to attack her, Haruka involuntarily attacks them with some gravity punches like those the iDols used, sending both girls to opposite sides of the arena. Seeing Haruka as a threat, many of the other girls in the tournament; Aya, Sanae, Sakuya, Reisen, Remilia Scarlet, Youmu Konpaku, Suika Ibuki, Fujiwara no Mokou, Iku Nagae, and Yuka Kazami, among others, attack Haruka, who ends up taking each one down with little or no difficulty. Before anyone else can attack, Yayoi yells out to everyone that they're not youkais or anything like that and to stop attacking. Everyone decides to do just that.
As the Imber-like armor disappears around Haruka and she comes back down to the ground, Reimu and Marisa decide to take Yayoi's word and let them be, realizing that the two of them are not from Gensokyo. Reimu asks the two just who they are, and Haruka explains that she is Haruka Amami and that her friend is Yayoi Takatsuki. Yayoi asks just where they are, and Reimu explains that they are in Gensokyo. At this point, Momiji Inubashiri, a wolf tengu that serves under Aya, runs into the stadium to explain to Aya about how just now, five strange objects crashed into various parts of Gensokyo and that the land is littered with strange shards. Momiji also brings up that she found a samurai, or better yet, what's left of her. Upon hearing this, Reimu decides that she'll go investigate just what happened and Marisa decides to go with her. Haruka and Yayoi ask if the two of them can go with them to figure out a way to get back home. Due to the tournament being cancelled, everyone else decides to go back home. Sanae decides to go back to the Moriya Shrine to see if everything is all right there after what had just happened while Sakuya heads back to the Scarlet Mansion hoping that one of those objects didn't crash into it. As everyone else leaves the stadium, Reimu, Marisa, Haruka, and Yayoi decide to head out to see what has just happened, especially since Haruka notices a glow coming from her key to Imber. Little do any of them of know, a major adventure has just begun as as Reimu and Marisa help Haruka and Yayoi locate the rest of their friends that have ended up in Gensokyo, they'll discover that the iDol cores have also ended up here and will have to get them before dark forces do so.