Ten years before Shirou Emiya's and Saber's fateful meeting, Japan is the stage for the fourth Holy Grail War. Seven Masters, each with his own dreams, step forward to win the boon of the mystic relic. Into this fray comes Kiritsugu Emiya, the enigmatic "Mage Killer" who wants to use the Grail to make a better world. Can he, paired with the indomitable Saber win the War? Or will he fall to the ambitions of the other mages?
Hakaze, princess of the Kusaribe mage clan, has been betrayed and marooned on an island by her own people. They seek to revive the Tree of Exodus, an incomprehensibly powerful entity of alien origin, to save the world from the tyranny of its antithesis: the Tree of Genesis that powers their magic. Hakaze, however, believes their efforts put humanity in jeopardy; and with her power limited, she can only reach out to the world to beg for aid. Her call reaches Mahiro Fuwa, a young man grieving the mysterious death of his sister, Aika. He and his friend Yoshino agree to help - on the condition that Hakaze track down Aika's killer with her magic. The deal is made, and the battle that will determine civilization's fate is begun: but who will play the part of its villain, and who its savior?
1. Magic exists in both worlds, but only certain people can utilise it. The magic in both anime also require some form of sacrifice before the magician can equip it (i.e., tools that civilisation use in Zetsuen no Tempest, magical power in Fate/Zero)
2. The two main male protagonists in both anime seek completely different goals. However, in Zetsuen no Tempest, the two protagonists are friends. Also, all four characters from the respective anime are really intelligent.
3. A lot of planning and plotting are involved in both anime. All the planning and execution are really intriguing and entertaining.
In 2010, the Britannian Empire enslaved Japan using powerful mecha known as Knightmares; in the aftermath Japan was renamed Area 11, and its people began a hard and terrible existence. Lelouch, a Britannian student living in Area 11, has grown up hating the Empire and everything it stands for. One day, in the middle of a terrorist attack, Lelouch meets a mysterious girl who grants him the ability to control minds. Can he use his new power to fight for freedom, or will his hatred twist his good intentions into mindless acts of vengeance?
Both of these series involve loads of chracters making intricate plans against each other for various motivations. There is action and a supernatural element in both. Code Geass has a lot of high school age characters while Fate/Zero mostly involves adults, and there are more not-so-serious episodes in Code Geass. Code Geass has mechs while Fate/Zero has swords and sorcery. But they both have more plotting and gambits than you can count. If you like that aspect of one, you'll almost certainly like the other.
Have you ever felt like the world would be a better place if certain people weren’t around? Such grim daydreams might occur when watching the dismal daily news, but on one fateful day, Yagami Light finds that these daydreams can become reality. By pure happenstance, he comes across a black notebook entitled "Death Note", whose text within states that whoever's name is written on its pages will die. With the aid of the death god Ryuk, Light takes it upon himself to rid the world of its corruption, ushering in a new era of purity one death at a time. But as Ryuk foretells, Light's actions will not go unchallenged...
Both of these shows involve a ridiculous amount of plotting and tactical gambits. They both take place in a modern day setting, but both have a supernatural element involved. Fate/Zero has a lot more major characters and different motivations whereas Death Note has a 1v1 feel, but there is a life-and-death competition in both and plenty of suspense as you wonder what the characters have up their sleeve next.