Mahabharata 7.158.41

उपदिष्टो वधोपायः कर्णस्य गुरुणा स्वयम्व्यायच्छतश्च खड्गेन द्विधा खड्गं चकार ह

upadiṣṭo vadhopāyaḥ karṇasya guruṇā svayamvyāyacchataśca khaḍgena dvidhā khaḍgaṃ cakāra ha

Our plain-language meaning of this verse is waiting for scholar review.