If you're looking for anime similar to Gin-iro no Olynssis, you might like these titles.
In the near future, Mars is covered with oceans. Within one of its cities, Gram River is just another kid trying to survive in the slums, until he finds himself right in the middle of a pirate attack! After nearly drowning, he finds himself aboard the pirates' ship, and is faced with a decision: be killed, or stay and fight alongside them. And thus, Gram joins the pirate crew in their quest to find the legendary treasure of Mars, but they aren't alone in their search. Now, while being hunted by the military, bounty hunters, rivals and even a few old friends, they search the seas of Mars for clues...
First off, theres a few basic similarities in the story lines:
Both of the heroes in the story find their mechs underwater after being atacked by enemy mechs.
Both the of the heroes travell around in a crew, and are romantically involved with some pretty weird people....
The stories are pretty simple and easy to understand, a little bland at times, but the pace picks up after a while. There are a few twist that made my jaw drop, but they were awesome!!!
As an orphan whose life is in the hands of space pirates, Coud has had no choice but to survive on bravado alone. He has nothing to live for until he finds Ren entombed amongst the treasures in the pirate ship's hold, and awakens her. In addition to being mysterious and beautiful, Ren can transform into a battle sword to help Coud fight and prove his strength -- but with this strength comes the bitter realization that power alone is not enough. Now, in a race against time, Coud must endure betrayals and fierce battles as he struggles to return Ren to her home, before it's too late...
AD 2019: the giant mecha known as LINEBARREL falls to Earth, grabbing the attention of the anti-machina organization JUDA. Before JUDA can arrive on the scene, an unfortunate accident occurs: LINEBARREL crashes into Kouichi Hayase, a weak and frail pushover of a boy. Waking up underneath a beautiful naked woman, Kouichi discovers that he now possesses great power and can summon LINEBARREL for his own purposes. All Kouichi has wanted is to become a hero of justice and hold his own, instead his childhood friends Yajima and Risako fighting his battles for him – and now he finally has that chance. With LINEBARREL's power, Kouichi becomes cocky and aggressive, lashing out at those he cares about most; and as a 'hero of justice', Kouichi must find his new place in the world and protect himself from two organizations who want their hands on LINEBARREL.
In both cases for the male protagonists, soon after meeting a strange girl with missing memories, they begin piloting an outstanding mecha with unmatched power on the side of justice with her. While the leading male character from Gin-iro no Olynssis has a nickname of Koichi, in Kurogane no Linebarrels, the head male character’s name is also Kouichi. How more alike can you get when it comes to characters and introductory plot?
Three years after an accident that nearly left him for dead, Tomoharu Natsume is about to start his high school life. Though with a ghost named Misao following him around, Tomoharu is far from being an average teenager. One day a strange woman appears and gives him a trunk that contains a tremendous power. This power is known as an Asura Machina - a being that draws its strength from a human sacrifice - and the sacrifice within Tomoharu's Asura is none other than Misao. As the bearer of such a power, Tomoharu immediately becomes the target of various groups, including the Divine Guards, who want his power for their own. When Tomoharu befriends a demon called Kanade and she is captured by the Divine Guards, he joins the Dark Society in order to save her. Now, Tomoharu will have to fight alongside the Dark Society while he tries to find a way to save Misao and bring her back to life.
Girls sacrifice their past, present, and future in order to become nonhumans/mechas in these sci-fi tales about females wanting to protect who is important to them - a guy. The males are fairly useless/pathetic in these for forcing the battling to take place between others (the girls they like). Includes slight romance in each.
Average, boring, and nothing special; this is how Shiratori Kuu feels about herself and her life as a high school student in Academia. On what begins as any other day, Kuu's life is spun upside down when a new student transfers to her class. As soon as she sees his face, she is astonished, for this is no ordinary boy – he looks just like the prince she has dreamt of for so long! He extends a hand to her and repeats the words she has somehow heard before, "Lets go... Together." But it is never that easy, is it? A world that seemed so dull is now torn apart by a whirlwind of love and hate, and the conflict that plagues all those involved.
Girls sacrifice their past, present, and future in order to become nonhumans/mechas in these sci-fi tales about females wanting to protect who is important to them - a guy. The males are fairly useless/pathetic (more-so in Gin-iro) in these for forcing the battling to take place between others (the girls they like). Includes slight romance in each (more in Shattered Angels).
It has been a hundred years since the end of the war between the Imperial and Republic armies. Humanity is spread out across the barren landscape, isolating themselves for better protection against the 'beasts' – rogue robots that are bent on wiping out mankind. But recently the attacks have been increasing in scale and frequency, and a wardroid-raised boy named Ital finds out why: the 'beast-masters', the part-human and part-robot controllers of the beasts, have returned. Together with his companion Zaxon, a wardroid who has lost his memory, Ital fights against the beast-masters. Why have they returned after so long, what are they up to, and who is this mysterious 'General' that they refer to?
In the year 2047, the invaders came without warning, annihilating most of humanity in days. And while the survivors banded together to form a new world government to combat the threat, by 2053, mankind's outlook is bleak. Now, in a final desperate attack, hope lies only with a soldier who lost his father in the invasion, and a weapon more powerful than belief.
As the result of heavy pollution, mankind now lives in remote and desolate locations in order to survive. The government rules with an iron fist, keeping close control over the masses. Gainer is a boy who has been playing a video game so much that he has finally secured the title of King. However, the next day he is falsely arrested for allegedly starting an Exodus – a journey to the mythical paradise known as Yapan. While in prison, fellow prisoner Gain offers to help Gainer escape, so with nothing to lose Gainer finds an Overman and makes his exit. However, in order to return the favor, Gainer chooses to further Gain’s cause: protecting the Exodus movement, even though Gainer’s parents were killed for their anti-Exodus ways…
Mankind is close to being wiped out from the face of the earth from a being known as Festum. Tatsumiyajima Island is a calm place where children can live their lives at peace, but the inhabitants must now move into combat to keep the citizens safe from the Festum assimilating them. Kyo and Yumi are average students who have signed up for Plan L: an operation to fight for their island using the new Fafner TSX model. Together, the 8 pilots and 4 Fafners will fight to preserve both the peace of their island, and their faith that one day, they will make it home… alive.
In 2029, a massive earthquake destroyed Tokyo; in the present day, its residents are still trying to pick up the pieces. Out to assist is DC, an organization charted with conducting research and cleaning up the city with the help of giant robots. Ken is a young man who has been training to get into the DC, but fails to be accepted into their ranks. However, when a giant white robot materializes, Ken jumps into action and subsequently is accepted into DC's ranks. Joined by his friend Mizuki, entitled Lyune and other new recruits, Ken tries his best to protect the city against the white monster. But soon, Mizuki is pulled into another dimension and returns with the startling truth behind the robot - and when attempts are made on Mizuki’s life, it becomes harder and harder to tell who the real villains truly are...