Amp Explanation

'It seemed so powerful. Why hasn't anything else worked that well?' 'I'm not sure.' Raoden said. A few moments earlier he had hesitantly redrawn Aon Ehe with the same modifications, creating the complex rune that was supposed to form another column of flame. Instead, the Aon had barely sputtered out enough fire to warm a cup of tea. He suspected that the first explosion had something do with the Does surge through him ... an expression of its long-awaited freedom. 'Perhaps there was some sort of buildup in the Dor,' Raoden said. 'Like a pocket of gas trapped in the top of a cave. The first Aon I drew drained that reserve.'

Elantris Chapter 19