"Seed Syllable of The Kalachakra" ,

Kalachakra_Tantra
Seed Syllable explained I was fascinated by seeing this 'occult knowlege' symbol in many places throughout my stay, it was very mysterious to me, i even had my friend's bhutanese painter husband include it in the thangka painting he made for me, which i then bartered for with my hoyt ultratec compound bow. :)
kalachakra blackened at thadra goenpa/lhakhang above yangchenphu