Wild magic

Wild magic zones were areas where the Weave was damaged or distorted. In such areas, a spell could backfire upon its caster, target the wrong location, be dramatically increased in power, or indeed, anything could occur. These areas were thought to have been caused by the titanic battles of the gods during the Time of Troubles. Wild-magic zones were the first areas where raw magic burst forth in the Spellplague.

Wild mages and the school of wild magic
Thorough study of the wild magic zones after the Time of Troubles led to the young spellcasting tradition of wild mages, who learned to tap directly into the raw magic of the Weave, independent of location. To access this power, they relinquished some of the control exercised by conventional mages and accepted the fluctuating and sometimes chaotic results of their spells. The spells of their school of wild magic were open only to these specialists. As a way of powering spells different from the traditional schools of magic, wild magic was considered a school of thaumaturgy. It was not opposed to any other schools.

Wild surges
While spells from the school of wild magic often had a certain element of chaos within them, they still had definite mechanics and purpose. However, for any spell a wild mage cast, there was the danger that they lost control over the raw power they utilized and released it in what was called a "wild surge": the freed magical energy either influenced and distorted the intended spell, or produced a totally unpredictable additional effect.