Indra is a god of lightning and thunder and storms. He defeats the drought-demon known as Vritra, saving the world by bringing the rains. As his weapon, he wields the thunderbolt (vajra), and his vehicle (vahana) is the celestial elephant Airavata.
In the epics, Indra is the father of the monkey-king Vali in the Ramayana, and in the Mahabharata he is the father of the hero Arjuna, one of the five Pandava brothers.
Here is Indra and his consort Shachi riding on the elephant Airavata: