Our main protagonist and actually The Lancer of the team, Eiji is a hot-tempered school boy who is looking for his missing sister Ayaka, only to find himself recruited into the Earthgertz as one of the Gran Knights of Sandman. He ends up being the 'voice of reason' to the clueless main pilot Touga, due to them being boys.
- Achilles in His Tent: In the first season, after Touga attempts to Shoot the Dog and kill Cecile along with the Zeravire of the week.
- Foil: To Touga.
- Get A Hold Of Yourself Man: Gives one to Touga in Zwei.
- The Lancer: To Touga. If he wasn't, Touga wouldn't have learned restraint in combat to prevent casualties in the first place.
- Master of Disguise: Can disguise as a woman believably enough to get other men to flirt with him, much to his chagrin. He even uses actual prosthetic breasts to help things.
- Red Oni, Blue Oni: Red to Touga's Blue, being more emotional and hotblooded than the more reserved and polite Touga.
- Restraining Bolt: Part of the reason he was brought in as a Grand Knight was because they did such a good job raising Touga to fight at the exclusion of nearly everything else, that Touga didn't know how to avoid casualties and collateral damage when actually fighting, and the other Knights were too into the I Did What I Had to Do mentality to even think of getting him to stop, or just didn't know any better either.
- Supporting Protagonist: He's the protagonist, but Touga's the leader.
- Vitriolic Best Buds: With Luna. Eiji rarely ever misses picking on Luna for being too violent or hotheaded for a woman (and she returns it by pointing out his moments of stupidity) and they tend to argue A LOT. But when push comes to shove, Eiji still considers her one of his best friends.
- Wholesome Crossdresser: Eiji ends up wearing a dress quite often over the course of the series(at least twice of his own volition), and is always pretty chill about it.
The main pilot of Gravion, Touga has been raised since childhood for the job, handpicked from his original orphanage by Sandman himself. He lived a sheltered life, therefore came off as naive and clueless on many things, but he had a good heart.
- The Ace: Trained all his life since childhood to pilot the Gran Kaizer and the Gravion. This is NOT a good thing, in spite of how polite and well mannered he is.
- Chaste Hero: Not really by choice, but mostly because he doesn't QUITE get romance yet due to his unusual upbringing.
- Child Soldier: All his life he was raised just to fight the Zeravire. One of the reasons why Eiji was brought into the fold was so he could have contact with another boy his age and help actually socializing in contexts outside of what he's used to in the castle. The other being because Eiji serves as a living Restraining Bolt to keep Touga from losing himself in fighting. Because he's so polite and well mannered, he just seems like a naive but pleasant airhead at first, his deeper issues not actually apparent.
- Deuteragonist: The show's other main character, after Eiji.
- Raised by Wolves: In episode 5 after stepping out of Saint Germain Castle with Eiji to visit the city, he shows just how isolated he has been from contact outside of the castle with how clueless he is regarding society, specially with how he doesn't seem the least bit perturbed by Eiji's method of sneaking out of the castle by dressing in drag AND using prosthetic breasts.
- Genius Ditz: Touga is an extremely skilled mecha pilot and commander... and also a complete airhead.
- Gone Horribly Right: At the beginning, he would focus solely on destroying opposing Zeravire unites and nothing else, not even so much as considering avoiding collateral damage or casualties. He nearly got Cecile, one of the younger maids, and Eiji, who is basically HIS BEST FRIEND, nearly killed during a zeravire attack because he wouldn't hold back on attacking while Eiji rescued Cecile from danger in the middle of a fight. It wasn't out of malice, he just didn't know any better because his training didn't cover anything BUT combat.
- The Hero: As the pilot of the Gran Kaiser, he is this despite not being the actual main protagonist.
- Princely Young Man: In spite of being clueless regarding normal human contact, he's always soft spoken and polite.
- Red Oni, Blue Oni: The Blue to Eiji's Red, being the more disciplined and focused of the two, at least in combat. In social situations, he's more polite and reserved than Eiji, who looks very crass in comparison, but not without warmth.
- Talking to Himself: With Lelouch Lamperouge and Luca Angelloni in Super Robot Wars Z2.
One of the two pilots of G-Driller that eventually forms up the arm. Luna is an energetic Okinawan girl that came to Sandman's group while looking for her missing father, which turned out to be one of the identities of Raven.
- Genki Girl
- Little Miss Badass: She's 14, just so you know. And yet, she's really fiery when it comes to battle.
- Rocket Punch: She's the go-to pilot that gets literally launched whenever Gravion uses the Graviton Pressure Punch. She handles it much better.
- Talking to Herself: With Aoi Hidaka in Super Robot Wars Z2.
- Tsundere: Type A for Eiji, Type B for Touga.
One of Sandman's many-many maid and also another pilots of the G-Driller. Ena is more or less reluctant about battles, but did her best to maintain between fighting Zeravire and taking care of the castle. She's actually a prototype version of the machines that formed up the Gravion (Gran Divas), built in 50 years by Sandman. After committing a Heroic Sacrifice, she was put back in her original body and rejoined as if nothing happened.
- Heroic Sacrifice: To save Touga, in Zwei.
- Proper Lady: In sharp contrast to her copilot.
- Rocket Punch: Sometimes she gets literally launched for Graviton Pressure Punch. Unlike her copilot, however, Ena usually doesn't take it well, screaming out of her lungs whenever launched. Not even changing to her old body fixed that.
- You Gotta Have Blue Hair: Green, and later pink.
The token adult of the Gran Knights, Mizuki is an incredibly busty lady, a skilled hacker and overall reasonable individual who was a friend of Eiji's sister Ayaka and was also looking for her, though she likes to get knocked on beer. She's the pilot of G-Striker, forming one of the legs.
Or so it seems. Mizuki is actually a spy of the EFA, leaking the development info of Gravion so the Federation could catch up technology-wise, which led to the creation of Gran Troopers. She's not too pleased with her boss' aim for upgrade to be more or less one-upping Gravion out of pride, instead of combining their strength together, which disgusted her post retirement and made her return to the Gran Knights.
- Boobs of Steel: Far bustier than the other female grandknights and is the only one with any kind of hand-to-hand combat skills.
- Cool Big Sis: She is by far the big sister figure of the Gran Knights, since she's the token adult. Likewise, she's highly looked up by Faye as her big sis.
- Everyone Has Standards: When she completed her job as a spy, she was given a luxury residence to retire. But she doesn't exactly like the president she was spying for bragging on how the Gran Troopers built from her information was made to one-up the Gran Knights after a lot of time Gravion helped defending the Earth, she wanted her information to be used so the EFA can catch up and actually be of use in defending Earth, like being an equal to Gravion.
- Hidden Depths: If you get past her overblown fanservice elements, Mizuki is actually a little more insightful than you think. Read the spoilers peppered around her tropes to see why.
- The Mole
- Ms. Fanservice: Sole adult, gigantic boobs, alluring voice. Mizuki is the shining example of Obari female fanservice.
- Obfuscating Stupidity: Part of her Hard-Drinking Party Girl image is an elaborate act to hide she's very good with computers and an EFA intel officer.
- Pigeonholed Voice Actor: Yuu Asakawa as a Ms. Fanservice with large breasts. Surprising, eh?
- Token Adult: She's the only adult amongst the pilots of Gravion, though not amongst all of the Gran Knights (since Sandman and Raven/Ayaka are also adults)
- Unresolved Sexual Tension: Has a hefty amount of this with Eiji, who gets to see her rarely shown serious side, and whom she hits on repeatedly, both in private and in public.
A shy young girl that was holed up in one of the towers in Sandman's castle, with them being close and she had a pet ferret named Lolotte. Leele is the pilot of G-Shadow, a stealth plane that could turn into a boomerang and formed up Gravion's chest. Her parents died in a fire, and thus she has a fear towards fires... especially blue ones... Hm?
Turns out, that's not what her origin was like. Leele is actually the daughter of Zieg Zeravire AKA Sandman. The destruction of her planet in blue flames horrified her so much that she lost her memories and afterwards she was put on a stasis capsule and sent to a capsule, but arrived in a latter time after the arrival of Sandman. Afterwards, she had to fabricate a new past, such as being Sandman's niece... until her past came knocking.
- Shrinking Violet: She's chronically shy and had a hard time opening up with others due to a traumatic past about 'her parents died in a fire'. Of course, that's not her exact past...
- Why Did It Have to Be Snakes?: Blue Flames. It was a hint that her past isn't as it was publicly stated.
- You Gotta Have Lavender Hair
Klein Sandman (Zieg Zeravire)
The main benefactor of the Gran Knights/Earthgertz, a stylish, charming and shrewd billionaire businessman, owning his own private St. Germain's castle. Sandman is Leele's uncle and Eiji suspect that he has something to do with the disappearance of his sister Ayaka. He forms the Gran Knights and gives permission to their main weapon, the huge robot Gravion due to predicting the invasion of the Zeravire, and that only Gravion stood a chance against them.
And that's because he was one of the designers of the mech and accidentally created the Zeravire. Sandman is actually Zieg Zeravire, one of the chief scientists of planet Llambias. With his planet facing peril, he and his brother Hugi created a countermeasure that would be known as the Genocidron, and later the Zeravire. However, knowing the danger it presented, Zieg ended up opposed to the idea and tried to offer another solution, but that fell onto deaf ears and to prevent Hugi to go on with his more diabolical plans with the Genocidron, Zieg wrestled control of them, causing it to go berserk, kill Hugi and destroy his planet. With his creation, now known as the Zeravire, let loose, Zieg wandered the galaxy and arrived to Earth, bidding his time to create a countermeasure in case the Zeravire come to Earth, while taking the identity of Klein Sandman.
- Cain and Abel: The Abel to Hugi's Cain, due to marrying the latter's sister. Sandman is opposed to using his inventions to kill other people to solve their overpopulation crisis, while his brother is more towards using it to wage war.
- Death Seeker: In the end of the series, he's content in dying with his brother in order to atone for his sins of bringing the Zeravire into the world. The Gran Knights and everyone made him change his mind.
- Heroic BSoD: In Zwei. Ayaka!Raven snaps him out of it.
- Human Aliens: Sandman is not a native of Earth, he came from the planet Llambias.
- I Always Wanted to Say That: During a sortie, once Gravion finished combining, he suddenly declared the mech's name in a booming voice despite not piloting. When Raven asks, his reasoning is that he always wanted to introduce the titular mecha in an awesome way.
- Ignored Expert: He already knows just how dangerous the Genocidron system is, having been involved in its development and proposed an alternative to solve the Llambias problems. He got ignored for it and things escalate to hell for his planet.
- Immortality: He is at least four hundred years old, but is implied to be much, much older than that. He loses this at the end of the series, though, when he activates the Gran Sigma.
- Large Ham: He certainly knows a great style and flair, the stylish man he is.
- Luke, I Am Your Father: For the most part, he's presented as Leele's uncle. The truth is... Leele is actually his biological daughter, and he's trying his best not to let the truth come out just so it doesn't heap up to her trauma.
- Mundane Made Awesome: He has a tendency to make several normal things look a lot more epic than it is. His Face Framed in Shadow of telling the Gran Knights to combine not epic enough? He'll one up it by dressing in grand clothes, and issuing the orders while riding atop of a plane. Playing ping pong? He'll just own his oppositions with sandals, and also goes Calling Your Attacks while doing so.
Raven (Ayaka Shigure)
- Becoming the Mask: Anyone wearing the Raven mask gains access to the memories of past Ravens.
- Bifauxnen: This one, at least.
- Drill Sergeant Nasty: Especially from Eiji's perspective.
- Legacy Character: The present Raven is Eiji's sister Ayaka, the one before was Luna's father; it dates back to Sandman's assistant on his home planet.
- Transferable Memory: His mask.
Faye Xin Lu
- Voiced by: Saeko Chiba (JP), Stephanie Nodolny (EN)