The mana value of a melded permanent is calculated as though it had the combined mana cost of the front faces of each card that represents it. If a permanent is a copy of a melded permanent (even if that copy is represented by two other meld cards), the mana value of the copy is 0.
July 22, 2016 · Eldritch Moon
The converted mana cost of a melded permanent is calculated as though it had the combined mana cost of the front faces of each card that represents it. If a permanent is a copy of a melded permanent (even if that copy is represented by two other meld cards), the converted mana cost of the copy is 0.
April 8, 2016 · Shadows over Innistrad
When calculating the converted mana cost of an object with an {X} in its mana cost, X is treated as 0 while the object is not on the stack, and X is treated as the number chosen for it while the object is on the stack.
September 30, 2011 · Innistrad
When calculating the converted mana cost of an object with a hybrid mana symbol in its mana cost, use the largest component of each hybrid symbol.
June 17, 2011 · Commander 2011
When calculating the converted mana cost of an object with a hybrid mana symbol in its
February 4, 2011 · Mirrodin Besieged
When calculating the converted mana cost of an object with a hybrid mana symbol in its mana cost, use the largest component of each hybrid symbol.
October 1, 2010 · Scars of Mirrodin
When calculating the converted mana cost of an object with a hybrid mana symbol in its
February 1, 2010 · Worldwake
When calculating the converted mana cost of an object with a hybrid mana symbol in its mana cost, use the largest component of each hybrid symbol.