Shiva Purana
तदा महेश्वरस्तेषां मध्यतो वरवेषधृक् ॥ स्वलक्षणैर्विहीनांगः स्वयं यक्ष इवाभवत् ॥ ४७ ॥
Then lord Śiva assumed the guise of a Yakṣa and stood in their midst devoid of his characteristic features in the limbs.
english translation
tadA mahezvarasteSAM madhyato varaveSadhRk ॥ svalakSaNairvihInAMgaH svayaM yakSa ivAbhavat ॥ 47 ॥
hk transliteration by Sanscript