The affix varac in the sense of 'agent having such a habit etc.' comes after the verb yā when it ends with the affix yaṅ,
With the affix यङ्, the intensives of verbs are formed; as यायावरः 'a vagrant, an ascetic'. See sutra 1.1.58.,
यश् च यङः
Adhyāya 3 · Pāda 2 · Rule 176