The magician would use a spell or a mental power to contact the energy within a natural force, such as fire or light. He would then be able to take energy from the force, fueling his own reserves.
If a magician could devise a way to use element assimilation, he would have almost limitless power. If he used magic during the day, he could take in the power of sunlight to preserve his own energy. He could start an inferno by casting fire, then draw strength from it as the blaze spreads. In the hands of the wrong spellcaster, element assimilation could wreak vast amounts of destruction.
Heliomancy was a hypothetical type of Element assimilation that involved drawing power from the sun, from either heat or light.
Roles in the booksEdit
No one has ever been able to use element assimilation so far in the books, but Eragon discussed whether it was possible with Oromis. According to Oromis, no one has ever been known to be able to use the power (as most people can only steal energy by using their mental powers and elements do not have minds), but they would have almost unimaginable power from its use.