[Graeme Dice]

Well, from the description of the magic scale, it implies that it's the innate magic nature of the world that is altered. A magic scale makes magic take less energy, and makes the effects more noticeable. A drain scale on the other hand, takes the magic out of the world and makes it much more mundane. Magical creatures don't belong in a drain dominion, which is why vineman attacks, the discovery of gems, and other such events only happen in a positive magic scale.