Padangusthasana Dhanurasana (Intensified Bow Pose) registers as 43* on BKS Iyengar’s 60* scale of difficulty in Light on Yoga.
Padangusthasana Dhanurasana is a more intense version of Dhanurasana. Personally, I’m a long way away from mastering this pose! Notice how BKS Iyengar’s version has his elbows facing out (rathern than the eyes of the elbows, like me). In the full version if Padangusthasana Dhanurasana, you clasp each foot as if you were taking Eka Pada Rajakapotasana I on both sides of the body at the same time. Then, you extend your arms and legs as straight as possible. Once you can comfortably clasp both feet behind you at the same time in this particular manner, begin exploring Padangusthasana Dhanurasana. Until then, focus on Dhanurasana. You’ll get many of the same great benefits of the backbend, minus the complexity!