The Thunder god – Indra (god of sky and Rain) was one of the most prominent gods of the Vedic religion. Rig Veda, the oldest of the Vedic scriptures, celebrates him.Almost 1/3rd of the books are dedicated to him.
He is also known as Parjanya in Rig Veda.
Indra is one of the Dikapals (guardian of directions) and is the guardian of the East (Purva) direction
Indra’s mantra is “Oṃ Laṃ Indrāya Namaḥ“.