Alchemy (Fullmetal Alchemist)

In the anime/manga series Fullmetal Alchemist, alchemy is a technique used to transform one material into another (referred to as a transmutation). For most alchemists, performing a transmutation requires the use of a transmutation circle. In addition, all transmutations, except for those performed with the aid of the Philosopher's Stone, are subject to the Law of Equivalent Exchange.