Magic: The Gathering Comprehensive Rules Changes - Core Set - Ninth Edition to Ravnica: City of Guilds

Old rule (Core Set - Ninth Edition)	New rule (Ravnica: City of Guilds)
203.2e. [Click to view all changes.]
	203.2e. An object with one or more half-half mana symbols in its mana cost is each of the colors of that mana symbol, in addition to any other colors the object might be. Most cards with half-half mana symbols in their mana costs are printed in a two-tone frame. See rule 104.3.

Old rule (Core Set - Ninth Edition)

New rule (Ravnica: City of Guilds)

203.2e.

An object with one or more half-half mana symbols in its mana cost is each of the colors of that mana symbol, in addition to any other colors the object might be. Most cards with half-half mana symbols in their mana costs are printed in a two-tone frame. See rule 104.3.