What is breath of the eidolon?

Breath of the Eidolon is a resource item in the video game Warframe that can be acquired by defeating the Eidolon Teralyst, Gantulyst, or Hydrolyst. These massive creatures are found in the Plains of Eidolon on Earth, and require a group of players working in tandem to take down. Breath of the Eidolon is used as a crafting material to create various items such as Arcanes and Amp components, which are crucial for advanced gameplay. The drop rate for Breath of the Eidolon increases with the difficulty level of the Eidolon, with the Hydrolyst having the highest drop rate. It is a highly valuable and sought-after resource in the Warframe community.