Sukadev chants during a satsangs the Mantra Krishna Krishna Mahayogin. You'll find it in the Yoga Vidya Kirtan Songbook as No. 604:
Krishna Krishna Mahayogin
Sarvam Me Vasha Manaya.
The Krishna Krishna Mahayogin mantra is a mantra for confidence, courage and success. As well it is a mantra for protection, a mantra against negative influence and negative vibrations, thoughts and so on.