>Takahashi had promised himself that Yu-Gi-Oh! GX would be the last Yu-Gi-Oh! series. However, he was approached at the end of 2006 with the idea for Yu-Gi-Oh! 5D's. The production staff and TV board were long time associates and friends, who had spread Yu-Gi-Oh! to many people in the world, so Takahashi agreed, under the condition that this would be the last Yu-Gi-Oh! series. Despite this, 2 other series, Yu-Gi-Oh! ZEXAL and Yu-Gi-Oh! ARC-V have been made.
>Naoyuki Kageyama is the author of the Yu-Gi-Oh! GX manga.He mentions in his manga cracks that he dislikes Synchro Monsters and promised himself to never use one, as he prefers Fusion Monsters (namely "Elemental HERO" Fusions), much to his dismay when he found out that "Dark End Dragon" and "Light End Dragon" were going to be released as Synchro Monsters