In this chapter of Harivamsha Parva of Mahabharata, Rishi Kashyap composes a stotra praising Lord Shiva. The stotra describes various attributes and deeds of Lord Shiva. The stotra in one place mentions that Lord Shiva becoming Yati conquered wolves sent by Indra in the form of Yati:
शालावृकान्यो यतिरूपो निजघ्ने दत्तानिन्द्रेण प्रणुदो हितानाम् ।
विरूपाक्षं सुदर्शनं पुण्ययोनिं विश्वेश्वरं शरणं यामि मूर्ध्ना ॥ २-७२-३१
I seek refuge in the Lord of the Universe, and pay obeisance to him by bowing my head, who, becoming a Yati (ascetic), conquered the senses in the form of wolves, sent by Indra, who suppress the desirable qualities such as self-control, one who has an odd number of eyes (shiva), one who is beautiful to behold and one who has an auspicious origin.
Harivamsha also contains a reference to Indra himself attacking Lord Shiva on his neck, which is discussed here. But the above reference made by Rishi Kashyapa seems to be a different event. So, when did Indra send wolves to Lord Shiva and Lord Shiva conquered those wolves taking the form of a Yati?
