I didn't mean to imply that Nature needed to have ranged attacks so much as an inborn talent for dealing with them. The dark school has very little in attack spells, the closest being short range incantations that do direct damage, and their "ranged game" is enhanced by the cloak of shadows. Most opponents trying to hit you with a spell are in range.
The Tegu gets soldier level armor, the raptor gets an actual ranged attack, and an ability similar to this could be another work around. I'm suggesting that slower, less robust animals have a means to absorb some of the ranged damage coming their way, even if nature mages never see much in the way of having their own ranged attacks.
Other card/board games have a similar quality as well. MTG has green 'reach' to deal with the fact that, as a color, green isn't supposed to have its own flyers. In Heroclix, the fast characters that move and attack in one action usually have low range as a penalty. I like that Mage Wars is setting a tone for each of the schools.
