 आवार्य गगनं मेघो यथा प्रावृषि निर्गत:।तथामायां विकुर्वाणौ राक्षसावभ्यधावताम्।। 
  Like the clouds in the rainy season, the two rakshasas Maricha and Subahu, covering the sky through their power of illusion, came running to the sacrificial place.  