I'm designing a simple magic system for a small game I'm developing.
It's based around the classical elements (water, earth, fire air), plus a few of the more common combinations of the of those elements (poison, magma, sand, etc).
Every person has an internal and external way of interacting with one of those elements. For example, an external water destruction mage may be able to destroy aspects of water while an internal water destruction mage will have aspects of himself destroyed by contact with water.
For all intents and purposes all elements have a sense of self, and an aspect can be any trait about that element that it observes about itself. All elements have an aspect of existence, and usually any of their observable traits are target able. However, targeting the aspect of fish in a body of water only works if the body of water believes the fish to be part of itself. This makes external magic very finicky as it involves a lot of guess work. Internal magic is far more precise as the only aspects targeted are aspects of the caster.
The more specific the targeted aspect, the more concentration and intelligence it takes to destroy. By default, a mage targets the existence of an aspect. For example, destroying the existence of water in a bucket will take little to no concentration, but expend a fair amount of energy. Destroying the aspect of the oxygen of the water will require a fair amount concentration, but less energy.
Internal mages have a fair bit of control over their interactions. In this example, with enough practice and concentration the water mage is able to control what aspects of himself are destroyed by the water and to what degree.
Here's where my question comes in.
Right now, the main concentration of most internal destruction mages is to negate or at least minimize the destruction affect upon themselves, and it's seen as nothing but a debilitation. Is there something more useful they could use the ability for?