Aldnoah.Zero is a mecha Anime about Martians invading the Earth. The Martians are, however, not aliens but humans who happened to discover ancient alien tech on Mars. The Terrans are stuck as the underdogs in the series, forced to outsmart the Martians, who have insane technology.
The series has a strange storyline (downright contrived…) and weird worldbuilding, for good measure.

I thought the first season was pretty good, and I enjoyed it quite a bit. The beginning of the story is particularly well-put together, introducing the world and characters quite well. The relationship between the Martians and the Terrans (alongside an introduction to the power-imbalance) is presented to the audience well, allowing the audience to quickly grasp the situation. From the beginning of the war, the Martians come off as an overwhelming force and a terrifying threat to the Terrans. The opening move with their landing castles is so beautiful, it continues to bring me to tears.
Unfortunately, the perceived threat-level of the Martians decreases fast over the course of the series. This mostly stems from the fact the Martians are morons - an obvious and serious writing flaw.
I found the insert songs to be awkwardly inserted and poorly timed.
The second season pretends the end of the first season doesn’t happen by undoing most of it. Surprisingly, I didn’t mind this as much as I expected to at the time, but it irritates me more as time goes on. This is mostly because the ending of the first season is quite daring…and then the second season just undoes it. I’d compare it to Code Geass in this regard, as I believe it achieves the transition from the first season’s cliffhanger ending to the start of the second season better than Aldnoah.Zero. The second season generally fails to make the Martians as threatening as they were at the very beginning of the series. While there is a brief moment where the Martians start regaining their threat level, the series brings back the MC after his little break, and him and his robot eye completely destroy the Martians. I’d say this is a shame, as the series could have been much better in this regard.
I do think I overall still like the series, and I would recommend giving it a watch.

While I assume this is a military alliance, the series doesn’t make it entirely clear^A). It’s possible that the UFE are a federation or even a centralized state.
As the name suggests, they are based on the planet Earth, and their number one goal is to defend it from a second Martian invasion.
This…unclear organization was founded after the first Martian invasion. For whatever reason, they’re also involved in a lot of censorship, some coming off as needless.
Among the examples of their tampering:

• We don’t know almost anything concrete about the founding of the Empire of Vers. This includes not knowing the exact chronology, alongside not knowing the dates^B), or even what events led to their independence.
• The UFE hid the truth surrounding the Martian invasion - specifically the fact that Martians had landed on Earth. They’re also possibly hiding the technological disparity.

The main character and primary protagonist of Aldnoah.Zero. He’s something of a physics nerd, and this allows him to understand the individual quirks of each Martian Kataphrakt quickly; consequently he has killed many Martians.
He also uses a training Kataphrakt rather than a regular military one, purely because the training one has less armor and is thus lighter. Because all training Kats are colored orange, he became easily identifiable on the battlefield.
Kaizuka is so great at piloting that he quickly propels himself to legendary status among the Terrans and Martians, no doubt helped by his relatively unique Kat. It’s somewhat unusual the UFE didn’t use him much as a propaganda tool^C).

The naïve princess of the Martian Imperial family. Her attempted assassination led to the start of the second Terran-Vers war.
Over the course of the series she becomes less naïve^D). By the end of the series she ends the war through a less peaceful route.
I don’t really understand what her name means. Perhaps it’s something more than style.

Although it’s been a while since I’ve seen Aldnoah.Zero, I started to realize that there may be a writing issue related to her characterization. More specifically, I’m thinking that her character development may have been rushed, because her characterization in season 2 doesn’t line up with her characterization at the end of season 1 (if I remember these things correctly). Her character appears to have gone through a big change, despite her spending almost the entirety of the second season unconscious in a tube. It just doesn’t make much sense for her to have gone through a serious change like what we see.

He dies in the first few episodes. The only reason he’s listed here is because of his famous quote:

Fuck 火星人(かせいじん)(Martians)

An unusual case of a Martian who fights for the Terrans. Her family had been placed by a group of Martians on Earth with the goal of orchestrating a war between Earth and Mars. After accomplishing their mission, they all get murdered sans Rayet.
She gets saved by the Terrans, and then goes through some internal conflict, before settling on working with the Terrans.

This is the most important character in the entire series. A legendary hero of the Terran side and feared by the Martians. The Martians had feared him so much, in fact, that they called him the ‘Lion of Death’. After seeing his confident stature on the battlefield, Martians would flee in terror.
Mysteriously, Martian women swooned over him. This was mysterious even to the affected women. After the war, scientists had not been able to figure out what caused this effect on women. Theories ranged from his natural charisma to some form of chemical weapon, secretly developed by the Terrans.
Despite his glorious deeds in battle, Mustang 33 failed to survive the war. His country gave him a funeral fit for an emperor. Doubly unfortunate is the fact his name had been lost, all records of him had been destroyed sans those that referred to him as ‘Mustang 33’.
All pictures of him had been destroyed by the United Forces of Earth as part of their treaty with the Empire of Vers. Vers had feared the pictures would have been a dangerous influence on teenage Martian girls.

The Holy Empire of Vers is an absolute feudal monarchical empire located on Mars. I have no idea as to how much of Mars they actually control, but it doesn’t really matter, since they’re the only ones there.
The twist is that the feudal system is built around Aldnoah, rather than land ownership.

The Orbital Knights are 37 clans^E) that all live in what is left of the Moon in the Orbit of Earth. In theory, they are loyal to the Imperial Family of Vers, but in practice, they are only loyal to themselves, and will willingly betray the family if they feel like it.
They are highly militaristic, violent and trigger-happy. To be fair, sitting on the Moon for about 20 years far from home and close to the enemy would drive anyone insane. Doubly so if the enemy has easy access to water, while Martians constantly deal with water shortages.
Why would they stay on the Moon? Because they couldn’t get home after the Moon had an unfortunate accident. That, and they want to be ready for another invasion of Earth.

Unusually, he’s a Terran who had defected to Mars together with his father (who we never see) because his father wanted to study Aldnoah^F). He mirrors Rayet in this way, although I haven’t done much analysis here yet^G). Due to being saved by the Princess, he has a crush on her.
He had been continually abused by the Martians around him for being a Terran, so he entirely logically decided to become their leader.
He goes from staying with Count Cruhteo to staying with Count Saazbaum because the latter murdered the former. However, Saazbaum angered him after he shoots the princess so he pledges his allegiance to Saazbaum? After a brief time staying with him he murders Saazbaum after he had adopted Slaine, as a result Slaine inherits all of Saazbaum’s things and becomes the leader of the Martian invasion.
When you actually think about it, Slaine was pretty insane^H).
His story ends when Inaho captures him. So he gets imprisoned and blamed for everything. The media declares him dead. It’s depressing until you realize that he’s a bastard, and death probably would be what he deserves.

The Moon fucking exploded and now, it’s controlled by the Martians. The parts of the Moon that were blown off now form a ring around the Earth. That ring contains a number of stations owned by Martians and Terrans^I), which then fight against each-other.
The Moon used to be where the hyper-gate was located - the hyper-gate being a portal device. The hyper-gate is what allowed the first colonists to go to Mars^J), and it was later used by the Martians to start the invasion of Earth. However, the hyper-gate ended up getting overloaded by the Martians due to the insane size of their fleet. The result was an explosion that destroyed part of the Moon, the hyper-gate itself, a big chunk of the Martian invasion force, and their current Emperor - this final loss caused the previous Emperor to come out of retirement.
The Martians had no other means of quickly going to and from Mars at the time, which left the remnants of the invasion force in an awkward and isolated position. These remnants became the Orbital Knights.

Aldnoah is a mysterious technology that was left behind on Mars by a long dead alien race. To summarize what it is: it’s magic, and it can do almost anything. Despite this, the alien species that invented it did end up going extinct and the Martians can’t seem to solve their problems like water shortage, no atmosphere, not enough food, etc. This is odd, if we’re looking at it from a meta perspective, since Aldnoah is presented as a miracle technology.
Aldnoah appears to be something like an engine, rather than some collection of technologies (or a sci-fi name for magic). Exactly how it messes with the laws of physics is another thing entirely.
Aldnoah can only be activated by members of the Imperial family and those who are loyal to them. Only the Imperial family can activate it because the first Emperor was the first person to touch Aldnoah, which then registered his DNA, allowing only him and his family to activate and deactivate Aldnoah. If the person responsible for Aldnoah dies, or almost dies, then all the Aldnoah drives they activated will deactivate.
Now ‘loyalty’ means that a transfer of DNA must occur…although the series is vague about this, so it’s possible that there’s another method. Basically, a transfer of DNA needs to occur. If a member of the Imperial family kisses someone else, then that person gains the ability to activate Aldnoah. There’s also an implication that this can be taken away, but I don’t know how that would work.
There’s also an issue with this activation method, as, apparently, it’s possible to gain the ability to activate Aldnoah without the other party intending it. This is because Inaho gains the ability from the princess while he was performing CPR on her…and she was unconscious at the time^K). This raises several questions about the worldbuilding of the series - such as why the Emperor is even listened to in the first place…it may be easier to just lock him up and drink his blood or something to that effect. The fact this doesn’t happen means that there is a way for the Emperor to take the power away…but we don’t know what it is.

Maybe I’ll remove this section entirely.

• Official site
• American site
• The Wikia - Pretty bad, don’t bother.
• aniDB
• AniList Season 1
• AniList Season 2
• theTVDB
• TheMovieDB
• I think I heard SAO sound effects in the show. This isn’t that surprising since Aldnoah.Zero was made by A1 Pictures.
• Rumor has it the Martians eat children.
• This was one of the first articles I wrote for this wiki. As such, I decided to preserve the older version even if I think it’s bad.