to vomit Indra out. The battle continued and Indra was eventually forced to flee. Vishnu and the rishis (sages) brokered a truce, with Indra swearing that he would not attack Vritra with anything made of metal, wood or stone, nor anything that was dry or wet, or during the day or the night.

After this, Indra managed to befriend Vritra. Once, while Vritra was asleep on the seashore at twilight, Indra collected sea-foam as a weapon to kill Vritra, as it was neither wet nor dry, neither wood nor any metal