Mines of Knowhere

Mines of Knowhere enters the battlefield tapped.
When Mines of Knowhere enters the battlefield, return a land you control to its owner's hand,
then you may pay {1}. If you do, draw a card and discard a card.
{t}: Add {b}, {g}, or {u}.
Whenever Mines of Knowhere is tapped for
mana, add {c}.