Board Thread:Naruto Discussions/@comment-1512913-20170121174919/@comment-1512913-20170210115204

It's not really that special. Only two things make it special:
 * It's a singular eye instead of a pair
 * Sasuke can use powers of Sharingan along with those of Rinnegan simultaneously, without it overwriting the other doujutsu as in Madara's case