Agni Purana (Jyotisha Selections) · by Vyasa
Chapter 3 · Name Letters and Chakras
युद्धजयार्णवः (चक्राणि)
मोटयेद्युद्धकाले तु उच्चरित्वा(समुच्चार्य) तु विद्यया ।तार्क्ष्यचक्रं प्रवक्ष्यामि जयार्थं त्रिमुखाक्षरम् ॥ १९ ॥
In the full Agni Purana this is chapter 133, verse 19.
At the time of battle, crush the figure, after saying the spell. Now I will tell the Tarkshya chakra, with three-faced letters, for victory.
Simple meaning: Crush the figure at battle time after the spell. Next comes the Tarkshya chakra for victory.
क्षिप ॐ स्वाहा तार्क्ष्यात्मा शत्रुरोगविषादिनुत् ।
The Tarkshya spell Kshipa Om Svaha is said to drive away enemies, illness and poison.
करोति यादृशं कर्म तादृशं सिध्यते खगात् ।
For the troubled and the sick, the bird makes any work succeed. It also deals with every kind of poison.
तत्सर्वं नाशमायाति साधकस्यावलोकनात् ।
The poisons go away when the practitioner looks at them. Then one meditates on Tarkshya with two wings and a human form.