This card is considered to be a Mountain and a Swamp even while in the graveyard, library, or anywhere else. The text applies even when it is not in play. [Jordan 2001/10/13]
Conversion changes the entire land to plains if it is a mountain. [WotC Rules Team 1998/02/01]
Extended tournaments (see Rule 913) have banned this card since 2002/11/01.
Note - It has land type Mountain and Swamp as per errata, so it has the two abilities "{Tap}: Add {R} to your mana pool." and "{Tap}: Add {B} to your mana pool." [D'Angelo 2003/08/01]
