What is a Shadowfax?
In J.R.R. Tolkien's book, The Lord of the Rings, Shadowfax was the Lord of all horses. He was a descendant of the greatest horses of Middle-earth. Shadowfax was said to run faster than the wind. Shadowfax's coat glistens like silver; and by night it is like a shade, and he passes unseen..
Shadowfax was too wild to be tamed so he was given to the wizard Gandalf the White by the King of Rohan.
“There is none like to Shadowfax. In him one of the mighty steeds of old has returned."