Oracle

Enchantment 

Cumulative upkeep 1UU (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
If tapped for mana, Plains produce R, Swamps produce G, Mountains produce W, and Forests produce B instead of any other type.

Tournooi-info

Legal in: Vintage, Legacy, Commander

Officiele rulings

10/4/2004
If a player uses a text-changing effect to make a land type be listed as producing two different colors, the player tapping the land for mana can choose to produce mana of either color. But if it produces more than one mana, all mana is of the same color.

4/15/2013
If a land has more than one basic land type, the player tapping the land for mana can choose to produce mana of either color. But if it produces more than one mana, all mana is of the same color.

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