Here are my top picks for anime like Aldnoah.Zero. Keep in mind the list is in no particular order. Enjoy the recommendations!
C.E. 71: In the midst of war between the Naturals (OMNI) and Coordinators (ZAFT), a unit from ZAFT is dispatched to hijack the Earth Alliance’s newly developed mobile suits on the neutral colony of Heliopolis. Orb Civilian Coordinator Kira Yamato attends the technical college on Heliopolis. After ZAFT hijacks 4 of the 5 mobile suits, Kira stumbles upon the last one, Strike, forced to pilot it to save his and his friend’s lives. During this confusion, Kira also reunites with his childhood Coordinator friend, Athrun Zala, who ironically turns out to be a ZAFT soldier and one of the hijackers at Heliopolis. Having control of Strike, Kira joins the Earth Alliance boarding the ship known as Archangel, to protect his friends while despairing over becoming the enemy of his childhood friend and people.
One day, a mysterious virus appeared on Earth which killed every infected human over the age of 13. At the same time, vampires emerged from the world’s dark recesses and enslaved mankind. Enter Hyakuya Yuuichirou, a young boy, who along with the rest of the children from his orphanage, are treated as livestock by the vampires. Even in captivity, Yuuichirou dreams big. He dreams of killing vampires. He dreams of killing them all. (Source: Population Go)
The story takes place in Tokyo in 2039, after the outbreak of the “Apocalypse Virus” during what became known as the “Lost Christmas” of 2029. Since then, Japan has been under the control of the multinational organization called GHQ.
Ouma Shu is a 17-year-old boy who mistakenly obtains a rare and great power. He can use this power, “The Right Hand of the King,” to extract “voids,” or tools/weapons that are the manifestations of peoples’ hearts. He has been rather shy since a childhood tragedy, but both his personality and life change forever when he meets a girl named Yuzuriha Inori, a member of the rebel group called “the Undertakers,” whose members seek the restoration of self-government in Japan via the ousting of GHQ.
It’s been a thousand years since the Gauna, a strange alien race with no known method of communication, destroyed the solar system. A portion of humanity managed to escape using enormous “seed ships” like the Sidonia, which have allowed them to maintain the population while drifting through space. Nagate Tanikaze is a young man who has been raised deep in the bowels of the ship. When he goes into training to pilot the huge robotic weapons known as Gardes, Nagate is entrusted with piloting the legendary unit known as Tsugumori. Nagate and his fellow pilots put their lives on the line against the Gauna, in the ultimate battle for the survival of humanity! (Source: Polygon Pictures)
Qwenthur came to the Alaskan military base to study Objects, the new weapons that have completely revolutionized war as we know it—battles are fought by soldiers controlling Objects far away from harm; however, when he starts to get close to Object pilot Milinda, will he discover the grim truth behind Heavy Objects?
In the year 2015, the Angels, huge, tremendously powerful, alien war machines, appear in Tokyo for the second time. The only hope for Mankind’s survival lies in the Evangelion, a humanoid fighting machine developed by NERV, a special United Nations agency. Capable of withstanding anything the Angels can dish out, the Evangelion’s one drawback lies in the limited number of people able to pilot them. Only a handful of teenagers, all born fourteen years ago, nine months after the Angels first appeared, are able to interface with the Evangelion. One such teenager is Shinji Ikari, whose father heads the NERV team that developed and maintains the Evangelion. Thrust into a maelstrom of battle and events that he does not understand, Shinji is forced to plumb the depths of his own inner resources for the courage and strength to not only fight, but to survive, or risk losing everything.
On August 10th of the year 2010 the Holy Empire of Britannia began a campaign of conquest, its sights set on Japan. Operations were completed in one month thanks to Britannia’s deployment of new mobile humanoid armor vehicles dubbed Knightmare Frames. Japan’s rights and identity were stripped away, the once proud nation now referred to as Area 11. Its citizens, Elevens, are forced to scratch out a living while the Britannian aristocracy lives comfortably within their settlements. Pockets of resistance appear throughout Area 11, working towards independence for Japan.
Lelouch, an exiled Imperial Prince of Britannia posing as a student, finds himself in the heart of the ongoing conflict for the island nation. Through a chance meeting with a mysterious girl named C.C., Lelouch gains his Geass, the power of the king. Now endowed with absolute dominance over any person, Lelouch may finally realize his goal of bringing down Britannia from within! (Source: Bandai Entertainment)
References: Wiki, MyAnimeList, ANN