What is Loki used for in Warframe?

Could you please elaborate on the purpose and function of Loki in the game Warframe? As a cryptocurrency and finance professional, I'm intrigued by how virtual currencies and assets are integrated into gaming platforms. Is Loki a form of in-game currency, or does it serve a more strategic or gameplay-enhancing role? How does its use impact the overall experience for players, and are there any specific scenarios or challenges where Loki becomes particularly valuable or essential?