Where does “проказничать” come from?

проказничать (Russian) comes from Russian прока́за, from Old East Slavic проказа, from Old Church Slavonic проказа, from Proto-Slavic *prokaza.

Ancestry of “проказничать”, step by step

Step	Language	Word	Meaning
1	Russian	прока́за	—
2	Old East Slavic	проказа	—
3	Old Church Slavonic	проказа	—
4	Proto-Slavic	*prokaza	—

проказничать — Etymology, Origin & Word History | Etymology Explorer