Ravana's maternal grandfather, Sumali, always hoped Ravana would reclaim the golden city of Lanka. "Take the city from Kubera!" Sumali urged. "Let it be a rakshasa city again as it was long ago."
Ravana's general, Prahasta, agreed. "The devas were wrong to drive the rakshasas from Lanka, and we are right to take it back."
Ravana sent Prahasta to Lanka as his emissary. "Give us back the city," Prahasta said to Kubera, "or we will fight you."
To Prahasta's surprise, Kubera yielded the city. "I will go to the Himalayas," he said. "Tell my brother that golden Lanka is his."