Fullmetal Alchemist, Volume 1

In an alchemical ritual gone wrong, Edward Elric lost his arm and his leg, and his brother Alphonse became nothing but a soul in a suit of armor. Equipped with mechanical "auto-mail" limbs, Edward becomes a state alchemist, seeking the one thing that can restore his and his brother's bodies...the legendary Philosopher's Stone.

Alchemy: the mystical power to alter the natural world
something between magic, art and science. When two brothers, Edward and Alphonse Elric, dabbled in this power to grant their dearest wish, one of them lost an arm and a leg...and the other became nothing but a soul locked into a body of living steel. Now Edward is an agent of the government, a slave of the military-alchemical complex, using his unique powers to obey orders...even to kill. Except his powers aren't unique. The world has been ravaged by the abuse of alchemy. And in pursuit of the ultimate alchemical treasure, the Philosopher's Stone, their enemies are even more ruthless than they are...