by Smash62bill
Mana Storm strong effect says: Reroll all dice in the Source. You can use three extra dice from the Source, and you can use dice showing black or gold as mana of any basic color, regardless of the Round.Surely you would be permitted to play this effect and reroll the dice in the Source so long as you didn't use the three extra dice?
And what if a hypothetical effect gave you one mana token matching each die in the Source, surely this isn't "using dice from the Source".
And consider the strong effect of Mana Pull: Take a mana die from the source and set it to any color except gold. Gain two mana tokens of that color. Do not reroll this die when you return it to the Source.
The first sentence isn't "using" a mana die: Yes, it does say "take", but you're only changing the face of the die and then later putting it back--you never use it as mana. The second sentence is merely using the die passively as in the hypothetical case I stated before it: the second sentence is merely giving you two mana tokens--and those are what you're using.