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Yidam es el nombre de una divinidad Budista, de la mitología Hindú
"HEVAJRA is a YIDAM, or tutelary god, worshipped in Mongolia, Cambodia, Thailand and Tibet, He is usually represented with four legs and eight heads; his body is blue, and his heads are different colors. He is sometimes shown alone, but often in Yab-Yum, the posture of embrace, with his SHAKTI or corresponding female energy."
Fuente: http://www.azibaza.com/lecture/lectures_indian_myt-h.htm