<P> `` Father '' ( お 父様 , Otō - sama ) is the creator of all homunculi using flawed aspects of his personality , and is the series ' central antagonist . He was originally known as `` The Dwarf in the Flask '' ( フラスコ の 中 の 小 人 , Furasuko no Naka no Kobito ) or `` Homunculus '' ( ホムンクルス , Homunkurusu ) , a shadowy , charismatic creature created eight centuries ago in Cselkcess ( クセルクセス , Kuserukusesu , `` Xerxes '' in the English anime ) under the commission of its king to obtain infinite knowledge . Confined within a flask where it can thrive , Homunculus formed an attachment to the young slave boy whose blood had been used in his creation , naming the lad Van Hohenheim , educating him and enabling him to rise up the social hierarchy . However , Homunculus grew envious of the human race , jealous of their mutual emotional support for each other whilst he grew lonely , being the only one of his kind . This envy caused Homunculus to lose sight of his own gifts and talents , eventually losing much of his self - confidence , and as he disliked this low self - esteem of his , he filled himself up with hubris . Playing on the vain King 's desire to become immortal , Homunculus tricked the king into creating a country - wide transmutation circle for the creation of a Philosopher 's Stone , whose necessary ingredient is the souls of several living human beings . Once activated , Homunculus ensured that he and the unaware Hohenheim were in the center , absorbing the souls of the population from Cselkcess between them . During the process , Homunculus used Hohenheim 's blood within him to create a humanoid husk body to serve as his mobile vessel before parting ways . </P>
who is the father in fullmetal alchemist brotherhood
the creator of all homunculi using flawed aspects of his personality