Gauntlet of Might
Artifact
Red creatures get +1/+1.
Whenever a Mountain is tapped for mana, its controller adds an additional 
.
Daniel Ljunggren
Magic Online Promos (PRM)
• #65656Rulings
Dual lands which have Mountain as one of their types produce an extra red mana when tapped for either color.
(wotc • 2004-10-04)
Rulings
Dual lands which have Mountain as one of their types produce an extra red mana when tapped for either color.
(wotc • 2004-10-04)