A Defiling move for Dark Sun:
Add up to half the spell’s level to your Cast a Spell roll. Defile an area, in a radius equal to the level of the spell, of plants and small creatures (insects, small lizards and birds, etc).
Double this area to defile only plant matter if present.
Halve this area to defile only higher order creatures and people if present; the latter, including you, take total damage equal to your adjusted roll (allocated as you desire). You may choose to take no damage from this move but each other creature or person that takes damage in this way must suffer at least 1 point.