Second attempt at a mechanic to add to the mana pool. White likes combat tricks, enchanting, and equipping creatures, so maybe a heroic mana gen ability?

The first con is that this iteration would go infinite with zero cost artifacts. Noting that, I will make the requirement be the creature must be the target of a white spell or ability. At that point, I think it may be possible to discard the "you control" clause, because is having this creature get Oblivion Ringed or Sunlance'd really going to be a problem?