Niflheim

Niflheim enters the battlefield tapped.
{t}: Exile target card from an opponent's
graveyard. If a creature card is exiled this way,
add {u} or {b} to your mana pool. Otherwise, add
{c} to your mana pool.
"The first root, and the deepest, goes into the
underworld, to Niflheim, the place that existed
before other places."