Agni Purana (Jyotisha Selections) · by Vyasa
Chapter 2 · War Astrology: Yogas, Nakshatras
युद्धजयार्णवः (योगाः नक्षत्राणि)
पूर्वभाद्रपदा सौम्ये रेवती ईशगोचरे ।कोटस्याभ्यन्तरे नाडी ह्यृक्षाष्टकसमन्विता ॥ ८ ॥
In the full Agni Purana this is chapter 128, verse 8.
Purva Bhadrapada is in the north, Revati in the north-east. The line inside the Kota holds eight nakshatras (stars).
Simple meaning: Purva Bhadrapada goes north and Revati north-east. The inner line holds eight nakshatras.
आर्द्रा हस्तस्तथाऽऽषाढाचतुष्कं चोत्तरात्रिकम् ।
Ardra, Hasta, Ashadha and an Uttara are the four pillars in the centre of the fort.
एवं दुर्गस्य विन्यासं बाह्ये स्थानं दिशाधिपात्।) आगन्तुको यदा योद्धा ऋक्षवान्स्यात्फलान्वितः
The fort figure is complete. A fighter coming from outside succeeds if he has the right nakshatra.
कोटमध्ये ग्रहाः सौम्या यदा ऋक्षान्विताः पुनः ।
With good planets and nakshatras in the middle, those inside win. The one who comes from outside is beaten.