B't X

B't X (ビート・エックス, Bīto Ekkusu), pronounced "beat X" and stylized as B'T X, is a manga series, written and illustrated by Masami Kurumada. It was serialized in Shōnen Ace from 1994 to 2000. An anime adaptation containing 25 episodes was aired in Japan between April and September 1996, followed by a second season containing 14 episodes called B't X Neo (ビート・エックス・ネオ, Bīto Ekkusu Neo) which aired between August and November 1997. The anime series never adapted the whole manga series, and included instead a different ending with no conclusion.

Plot
Teppei Takamiya is the caretaker of a farm located in Kamui Island, north of Japan. His older brother, Kotarō Takamiya, leaves to study robotics in Germany and becomes one of the most brilliant scientists in the world. Five years later, the two brothers reunite at a robotics convention in Mechatopia, China, where Kotarō is to announce his latest breakthrough in artificial intelligence. The convention goes awry when Kotarō is captured by the malevolent Machine Empire and taken to "The Area".