Rudra is an important Vedic deity, and is considered to be an incarnation of Shiva. He is often referred to as the "Destroyer" or the "Furious One" and is associated with storms, wind, and destruction. He is also known as the "Lord of the Roar" and is often depicted with three eyes and four arms. He is also associated with the Rudraksha beads, which are believed to bring good luck and protection.
ēkādaśaitē rudrastu surabhitanayaḥ smr̥tā ।
Meaning-This eleventh Rudra is called the son of Surabhi. These are the abodes of happiness and have been born from the form of Shiva for the accomplishment of the work of the gods.
Shivpuran is one of the most important and most read Puranas among all the Puranas. In Shivpuran, eleven Rudras are described as an incarnation of Shiva under Shatrudriya Samhita. It is said here that being pleased with Kashyap's penance, Lord Shiva took birth in the form of eleven Rudras from the womb of Kashyap's wife Surabhi. The names given here are somewhat different from all the above lists-