Here are some mysteries of GateKeepers solved and unsolved by GateKeepers 21. Most info are from Chou Nuriko while some are from watching the OVA itself.

Mysteries Solved

Explanation of Gate

• Why Yukino does not age?
• Why GateKeepers have sad backgrounds?
• How does a gate affect its keeper?

A Gate is a door from another dimension where an ability and an energy can be summoned by a GateKeeper. To be born special with the ability to summon a gate comes with a heavy price. If at an early stage a Keeper is not aware of his ability the gate will absorb his happiness in the future. Note on the backgrounds of Shun (father died), Reiko (broken family), Kaoru (her ability was not recognized and was even disqualified for achieving impossible record on track and field), Fei (family was taken away from her by the government), Megumi (her insecurities towards Ruriko or someone better than her), Reiji (father got broke and dies while his uncle takes away their belongings), and as for Ruriko - her heartaches towards Shun and also her insecurities in life. On another case, if a GateKeeper overuses his power, the gate will consume his physical being or time. This explains Yukino's agelessness.

Yuurei Shoujo [Ghost Girl]

Yuurei Shoujo is actually a GateKeeper of Disappearance (her negative gate is the Gate of Regeneration) who is the main villain in the GK21 OVA. She is originally a character in the game, with blue hair, white gown, and holds a skull. In the OVA she had yellow hair and a crystal ball. She is actually dead because when she was alive she overused her gate.

 

Questionable

• Who's Ayane Isuzu's mother bearing the Isuzu as her maiden name?

  [UPDATE]: Ayane Isuzu's mother is not from the original TV series (therefore not Ruriko Ikusawa) as revealed by GateKeepers 1985 novel

  [UPDATE]Chad Kawakami shares this interesting information:

  The original first-pressing Japanese DVDs for Gatekeepers 21 came with a CD audio drama. Gatekeepers 21, Ep. 2 came with Audio Drama CD "Episode 0.8 Satoka". At the end of the drama, there's a brief question & answer session hosted by Manazuru, Miu. One of the questions she asks Isuzu, Ayane is who her mother is. Ayane's response is: Isuzu, Youko. Other than the name, no other comments are given.

• How was Reiji Kageyama able to survive the black hole in the final episode of GateKeepers series [not OVA]. (Refer to GateKeepers 1985 for the answer)
• Why and how did Shun Ukiya die? (Refer to GateKeepers 1985 for the answer)

Theories

• Yukino has Hisame as her companion and it seems that whereever Yukino is Hisame is there. Hisame is as ageless as Yukino for he/she/it appears in GK TV series (set in 1969) and GK21 (2001) still in original form. So probably Hisame's a gatekeeper itself!
• Yuurei Shoujo is actually dead but still possesses a tremendous power, so we can assume that a Keeper remains a Keeper even at death, given the spirit lives on.
• It is said in GK21 that modern Invaders compared to the ones that appeared in GK TV series are organic or are humans. Well in GK TV series the Invaders are also human and their crystals disintegrate in seconds especially when touched, so restoring them to their human form is impossible. Killing Invaders in this series is more humane, because their crystals (which contain the essence of humans) do not disintegrate immediately even when touched. And AEGIS Network is collecting them and they are researching ways to restore them.
• The Invader Crystal Argument (Chou Nuriko)

  For the Original Invaders (a.k.a. Invader Bosses) and the Invaders in GK21, the crystal actually is the crystalization of their soul/core being. Yuurei Shoujo had once mentioned in GK1985 that as long as the crystal is not destroyed, the Invaders can always come back to life after a certain period of time (like Kikai & Akuma). But for one of the O.I. Jigen Maou, his "crystal" was destroyed by Jim, Jun and Misao, so he could not be revived again.

  At the very beginning, the Invaders were inorganic substance. Until later, they evolve and fuse into the human society at an even higher rate and eventually become organic by the year of 2001.

Additional Points to Ponder

1. Reiji Kageyama's right leg is disintegrated in the early part of episode six as he is bombarded with attacks from the invaders. Yet in the later part of the episode (when Ayane and Miu combine gate abilities), he is standing on two legs. Production error?

2. Ghost Girl's Minus gate seems to be the key to restoring the crytalized invaders back to human form. Why not create an imitation gate of it?

3. If a minus gate is simply the opposite of a regular gate, can Fei's (editor's note, I just noticed this was Kaoru--- I think this meant Fei---until I updated this page) gate be the minus gate of Yukino?

4. How exactly does Reiji Kageyama's gate work? I thought it just worked as perception (like misao's, only more powerful), and not as an offensive gate?

5. In ep 2, I noticed that Ayane tore the '69 GK pic between Shun and Kaouru, not between Shun and Ruriko. Is this supposed to imply anything?

Chour Nuriko's reply to cancheta @ svi.com.ph

1. Cool eyes!! I bet even the producer didn't notice that...

2. I guess it was because no one knew that such Gate existed before.

3. (reply added 1/7/04) To solve this question, we must look into the definition of a minus gate. The minus gate can only be opened when the GateKeeper is using his/her negative emotion and change the gate into the opposite of the original gate.

Brief study of the 4 majoy Black Gate Keepers in the series:

Gate keeper	Gate	Negative Emotion	=	Minus Gate
Kageyama	Discernment	hatred + anger		Darkness
Megumi	Iron Wall	jealousy + hatred + misery		Invasion
Ruriko	Life	hatred + perhaps misery		Genocide
Yuurei Shoujo	Disappearance	anger + perhaps jealousy		Regeneration

Whether a gate is a minus gate or not was decided by the GateKeeper's emotion rather than the gate's property. So we can't say Fei's gate is the minue gate of Yukino simply because fire can be the opposite element of ice.

4 . Kageyama's Gate of Discernment has the ability to forcefully absorb the happy side of future. In the case of battling Invaders, this the "happy future" will be the destruction of Invader. Being able to see the future should be a side effect of this power.

5.Ayane didn't tear the photo between Ukiya and Kaoru OR Ukiya and Ruriko — she tore the photo between Ukiya because she hated him. And it was revealed in GK1985 that Ayane's mother is not one of the GK Girls from the original series.

By Filbert Teo

4. The answer to question 4 (the one on how Reiji Kageyama's gate work) should be because what Reiji Kageyama's gate actually does is to predict the future. After that, he summons the future by the force of his will (or so he says in Episode 2)... So there you have it. =)

Chou Nuriko's counter-argument

4. A line from Kageyama "...My Gate of Discernment is different from the Gate of Perception, which can accurately analyze the physical phenomenon. The Gate of Discernment has the ability to take in the dim sight of future, and abstract the definite result from it..." (GateKeepers 1985, P.71)

...Which had made the point that the Gate of Discernment is NOT to predict the future. Just get a glimpse of it.