Shiva Avatars

Often, members ask if Lord Shiva has ever come as incarnation. 
Member Kumar Aurojyoti has sent this detailed information, saying:
Namah Shivaya!! I am hereby sending an article on Shiva Avatars that are described in Shiva Purana. The book I referred to for this work was “Shiva Purana” in Hindi published by Gita Press. If you like it, you can post it on my behalf for the benefit of all Shiva devotees.

Shiva Avatars

In the Shatarudra Samhita of Shiva Purana, various Shiva avatars are described. Lord Shiva has taken innumerable avatars. Only a few of them have been mentioned.
In the 19th Kalpa, called as "Shwetalohita" Kalpa, Shiva took the "Sadyojata" avatar. When Lord Brahma was meditating to get a son, a child was born whose body was shwetalohita or white & red. Then Brahma realized that he was none other than Shiva Himself and worshiped Him. Then in the 20th Kalpa called as "Rakta", Brahma was meditating to get a son. Then a son was born from him whose body was adorned with red garments and red garland. His eyes were red and also his ornaments. He was called as "Vamadeva".Then in the 21st Kalpa called as "Pitavasa", Brahma was again meditating to get a son. At that time a son was born from him who had worn yellow garments and had huge & powerful arms. Then Brahma came to know that he was Shiva in form of "Tatpurusha".Then in the next Kalpa the 22nd, Brahma was again thinking about creation when Shiva in form of a child appeared before him whose body color was black. He also wore black garment with a black turban in his head alongwith a black sacred thread around his body. His crown was even black and the sandal powder for applying in his body was also of black color. This avatar of Shiva was called as "Aghora".In the 23rd Kalpa called as "Vishwarupa", Brahma was again meditating to get a son, when Shiva appeared in form of a son called as "Ishana". His body color was white like crystal and he was decorated with all types of precious jewelry.