User summary: Green Lightning is a derivation of a standard "D20" base with numerous modifications and extensions intended to support play in a "Anime/Manga" style setting. The rules primarily grew out of the previously published One Piece: The Role Playing Game, but with much of the setting details removed and extensive additions to support multiple genres of play. The massive single document of the game includes materials that traditionally would be split into "Game Master" and "Player" guides, as well as a bestiary.