Enchant land As Convincing Mirage enters the battlefield, choose a basic land type. Enchanted land is the chosen type.
"Where are we? You must learn to ask more useful questions than that."
Official Rulings for Convincing Mirage
10/1/2009 : The affected land loses its existing land types and any abilities printed on it. It becomes the chosen basic land type and now has the ability to tap to add one mana of the appropriate color to your mana pool. Convincing Mirage's ability doesn't change the affected land's name or whether it's legendary or basic.
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