Opium, mountain-dwelling brother of storms

I am a man. My name is Opium. I dwell among the mountains. I am known by theIUMOOpoppium, and other mighty ones of the earth. The waves of the sea are my brethren, and I delight in their strength. I am present at the birth of the tempest, and aid in the labours of the child of darkness. The lightning knows me. I am opium.