Yin and Yang are 2 Dragons that look exactly the same like the 2-3 Mission Dragon, but they are both Spawns in Dynamis Xarcabard and are spawned in the fight against the Dynamis Lord!
Ying and Yang look exactly the same. If you ever seen Shadow Dragon, they are the same model. Go here and click on the Dynamis lord link. http://www.beyondthesky.net/modules.php?name=Downloads&d_op=viewdownload&cid=1