Manifestation

Shilad did a tremendous penance to please Lord Shiva. His penance continued for thousands of year. At last, Lord Shiva appeared before him and said--"I am extremely pleased by you devotion. I shall bless you with a son who will become famous for his knowledge and learning." But, Shilad was desirous of a self-born and immortal son. Lord Shiva said--'Your desire will be fulfilled. Even Lord Brahma had requested me to take an incarnation. I will take birth as your son and my name will be Nandi."

In course of time, Shiva manifested from the oblation site. The deities became pleased after seeing Nandi, who possessed three eyes, four arms and a crown on his head.

Source

Linga Purana

Mouth Water

https://www.google.com/search?site=imghp&tbm=isch&source=hp&biw=1280&bih=600&q=nandi+mouth+water
https://www.youtube.com/results?search_query=nandi+mouth+water

ishwara

https://www.youtube.com/results?search_query=Nandishwara

Yaganti

http://highwayonlyway.com/tag/yaganti-uma-maheswara-swamy-temple/

largest horn

http://en.wikipedia.org/wiki/Ankole-Watusi
https://www.youtube.com/results?search_query=Ankole+Bull

Staff

Vidyunmali

Nandi fought with Vidyunmali and slew the demon after a fierce battle. But Maya knew all sorts of magical tricks. He was particularly well-versed in the use of herbs. Maya gave Vidyunmali a bath in the juice of magical herbs and Vidyunmali immediately revived. This act greatly boosted the demons� morale and they began to fight with renewed vigour. Any demons who were killed, were instantly revived by Maya. But when Shiva himself entered the fray, the demons were put to flight. Even the herbs that resurrected dead demons proved to be of no avail. Nandi killed Tarakasura after a fierce duel. 

https://www.youtube.com/results?search_query=Vidyunmali

Source