Its been years since I've played this game, and I'm just reaffirming something. If you play an artifact or a special land card that allows you to retrieve a specific mana type and play it, is this ability limited to only being able to play one mana in a turn? Or is this something that you may do 'in addition to' this rule. For instance I play one red mana from my hand, then I tap my artifact "Prophetic Prism" wich allows me to tap it and tap another mana and add one mana of any color to my mana pool. Am I allowed to use this ability, or does the one mana per turn rule trump it?