It is said that Shiva evolved from Rudra with both of them having an unpredictable and potentially destructive nature. Also known as the divine archer, Rudra is said to fire arrows that bring death and disease. However, he is not simply a destroyer -- he has healing powers as well.
Rudra yoga is a type of Raja yoga, also known as Royal yoga. This type of yoga is said to deeply enhance the individual's spiritual practice when carried out at certain times on the astrological calendar and according to their own astrological circumstances.