Hall of the Alchemist

As Hall of the Alchemist enters the battlefield,
choose a card name.
{t}: Add {c}.
{1}, {t}: Add {c}{c}{c}. Spend this mana only to
cast a spell with the chosen name.
{3}, {t}, Sacrifice Hall of the Alchemist: When
you cast your next spell with the chosen name
this turn, copy that spell. You may choose new
targets for the copy.