This is what happens when diplomacy fails!
 
Only one piece of cake left… how could such a terrible thing happen? The Princesses of Equestria had come to the Crystal Empire on a friendly visit, but how quickly it had all turned sour. Though attempts were made to placate the warring Alicorns with fresh cupcakes, their battle was too far gone to be stopped. Soldiers from the Royal Guard stood by uneasily, the castle staff looking on fearfully. Not even Shining Armour had been able to intervene, forced to flee the field of battle, calling out bitterly “I am not cleaning that up!”
 
The crystal ponies will not soon forget the day their castle echoed with the sounds of conflict as the Princesses turned on each other. And it would come to be known as The Pillow Fight of the Princesses.  
… geez! This really made the headlines? Must have been a slow news day…