Opposing Powers
Sometimes the effects of magical abilities are directly opposed to each other. For example, an area of magical light cannot exist in an area of magical darkness. Similarly, a Wall of Fire cannot occupy the same area as a Wall of Ice. In some cases, a power will have a specific opposing ability, such as the case with Deity's Boon and Deity's Curse. For these powers, their opposing abilities will be specified directly on each power. In other cases, two powers can have opposing keywords, such as Fire vs Powers and Light vs Darkness. For these cases, the opposing factor is determined by the power's keywords.
Whenever two opposing powers come into conflict (typically when one power encounters the persistent effect of another ability), then an Opposed Potency check must be made. If the potency of the persistent effect succeeds, it remains and the opposing ability is effectively Dispelled. If the persistent effect fails, it is effectively Dispelled and the opposing ability functions as normal.