The best assassin among the high gods was the Goddess of Hidden Shadow, Martini. Her authority was in the field of shadows and darkness. But that doesn't just mean normal shadow but also other types of shadows like the shadow in someone's heart or simply gloomy feeling etc.
In RASHTROYNI there were a lot of things that can be associated with shadows, so the amount of power she hold was quite a lot. She had varied abilities matching almost all situations. Martini was one of the most versatile people among the high gods.
Her opponent was also someone from the same profession. She was the best assassin and spy among the devils and was also successful in infiltrating the world boundary and she was the only one who was able to do that.