[[WMG:The story is based on the author's traumatic game of ''VideoGame/XCom''.]]
Anyone who has played a nighttime terror mission can attest to the cycle of overconfidence -> sudden deaths -> confusion -> people running around in stark terror and dying horribly -> TotalPartyKill.
The author is just fictionalising events slightly. Hell, even the guns and battle armour look similar.
[[WMG:Gantz is a reality show for a bored omnipotent being]]
Think about it. Futuristic looking weapons and suits could not possibly be made with current human knowledge. Gigantic pods that give out points for the number of points being scored. An approaching apocalypse.
It would definitely make for one hell of a plot twist.
* Pretty close! Turns out [[spoiler:it's a reality show for politicians and the super rich, all based on the interpretations of the random numbers spewed by an idiot savant.]]
* Oh yeah, but that totally didn't seem dubious after [[spoiler:the German guide/otaku-extraordinaire started speaking in fluent Japanese and... then teleported away.]] Hmmm.
** only after causing mass destruction out of thin air
* judging by the attitude of said being, the entire alien invasion and gantz can simply be attributed to the fact that this "omnipotent" being has all but said that he is naught but the equivalent of a holographic projection from a higher dimension, and he is clearly just causing humanity misery ForTheLulz. What else would a bored, limitless, being do with what is effectively to it a sentient version of [[TomatoInTheMirror Sim-City]]
* as of the latest chapters, TheReveal is [[spoiler: that a sufficiently advanced alien species gave humanity the means to fight off alien invaders, just to spite said invaders (who were in a scuffle with our "benefactors" earlier). They only sent the technical specifications, it took a depraved human mind to craft a gameshow from that.]]
[[WMG: Kurono survived thelast anime mission.]]
Note that his pic didn't grey out like the others. It's possible that surviving gave him 100 points and got him released.
[[WMG: The aliens have something to do with religion.]]
Think about it. The Buddhist Temple Mission had alot of figures from the Buddhist religon. The Oni are important to the Shinto beliefs. The Osaka mission was almost entirely composed of monsters from old Japanese myths and beliefs. In the Rome mission, they were attacked by statues of angels and other religous figures. Coincidence?
* Not coincidence. RuleOfCool. Other ''aliens'' had nothing to do with religion: the folk singers slash birds, the Dragonball rip-offs, the elemental-powered slick dressers, the black knights (probably), the dinosaurs...
[[WMG: Concerning earth technology and aliens appearance.]]
The aliens invaders have threators amongst then,it's the only way for humanity to have access to that kind of technology,so sooner or later there will be an inside attack.OR they could have made the most terrific act of manipulation by giving humanity some of it's technology so the ycould take on the aliens living on Earth who could have been to only truly obstacle in their way,this way it also explains the behavior of the first aliens;The onion alien only attacked because the gantzers killed his son,the Robot Rock Lee's only attacked after Nishi killed one of its siblings/spawn,and the buddah aliens only attacked after the initial attempt at their lives after that rumors started circulating around the tokyo area about the alien hunters,so when Kurono appeared near the chibi alien it was already prepared to attack him, so this way the Invaders could herd out some of it's competition while thinking the humans would go down without resisting when they appeared what they did no expect was humanity crazy survivalist nature.
[[WMG: The creators of Gantz also gave us [[Anime/PuellaMagiMadokaMagica the Incubators]] to reach out to idealistic young girls.]]
Gantz appeals to jaded, debauched ([[TheUnfairSex mostly male]]) adults, while Kyubey handles naïve adolescent girls who only want to help others [[spoiler:(or at least they tell themselves that)]]. Yes, ''Madoka'' fans, you too have been watching a horrible TorturePorn ''[[spoiler:[[ImmoralRealityShow reality show]]]]'' all this time.
[[WMG: The revelations made at the End will start up an entirely new religion]]
Due to the recording session with the god-like aliens, every human will witness and learn the information it gave about [[OurSoulsAreDifferent three grams of data]] that reincarnates after death. Surviving skeptics will naturally caution the public about assuming this information to be true just because it came from a superior entity. After the technological advances made by researching Gantz and left over invader tech, they will conduct experiments that confirm the three grams of data theory. This will provoke a new religion based around such findings that will quickly supplant Judeo-Christian thought. Reincarnation will be accepted as a fact around the world. However this will not prevent human civilization from following the same hollow materialism that the Invader Civilization followed.