As the meditator moves toward the center of the mandala, he or she finds the second circle, a ring of flames in five alternating colors, which burns away spiritual obstacles. The third, smaller circle is a "diamond" (vajra) wall; it gives the power of pure consciousness. The fourth, innermost circle consists of lotus flower petals in five alternating colors that unfold spiritual vision. The meditator approaches the four-walled palace where the deities live after crossing these moatlike outer circles.