"Electrocuted."

While she'd only suffered a few shocks in her time, she understood that electricity could be debilitating even to a Slayer. And the havoc it played on the heart...

Once again, she glanced at his chest. "But you didn't stay electrocuted." Otherwise, he wouldn't be here right now. But it can't have been a simple case of not-death, else Sokka wouldn't have reacted like this.