The Undercity

If you control four or more nonbasic lands, you
may pay {0} and discard a card rather than pay
The Undercity's mana cost.
{b}{b}{b}: Target card in your graveyard gains
Dredge 6 until end of turn. Activate this
ability only once per turn.
The Undercity has all activated abilities of lands
and artifacts in your graveyard.