(card title) Mountain

You may have any number of '(card name) Mountain' in one standard Magic:TG deck.
Tap this card: Produce one mana of the "Red" type into your "mana pool". This Red source, deemed "{r}" or "Mountain" may be used in spells requiring "{x}", or "{p/r}". You may activate this ability during any players turn as a "Mana Source", used in casting spells. This card untaps at the beginning of its owners untap step during the "Upkeep" phase of the turn. Once this ability is activated, it cannot be countered