|Title||Duke Rough Diamond, Duke Diamond|
|Faction||Crystal Empire (Formerly)|
|Description||Xenophobic Against Changelings, Mean and Cruel, Fair But Firm, Treacherous, Supportive But Deceptive|
|Skills and Abilities||Natural Magic Abilities, High-Grade Magic And Masterful Deception|
|Status||Turned into a Changeling|
Duke Rough Diamond is an Equestrian Unicorn and the former non-Crystal Duke of the Crystal Empire. He comes from a land where Changelings succeeded in manipulating their rulers into passing their kingdom to them, leaving it all to die, and for Rough Diamond to become bitter since he was in love with a Changeling named Vana, only to find that she betrayed him to allow Queen Chrysalis to consume the land, refusing to listen to her when she was trying to explain that she didn't wanna be a part of that because she was starting to open up to him, and even turns her into Chrysalis when she tries to explain again. Since that day of betrayal, he grew into a stuck-up and rude jerk who accepts the mistreatment that Changelings get, and wishes to see them all die or go away. Ever since moving to the Crystal Empire, he has been trying to enforce a ban on Changeling interaction and even attempted to declare a genocide. However, Destiny the Changeling views Diamond as a very dishonorable person for not listening to reason because of hate, and even declares it a hate crime, especially when she rescued Vana from being executed by Chrysalis following his deporting. Despite his bitter personality and hateful edge, he can still be told off with the right words. And eventually, the Duke will seen an incoming downfall.