The Wailing Tower

In a time shortly after the Wall was built, the great wizard Hurstis wandered out into wilderness. He had been a great man. He had been instrumental in the expansion of the Empire, and it's quick decline.
Hurstis had appeared when the Empire was at war on all its borders. He helped then Emperor Milleus hold one front, while another was assaulted, both through his use of battle magic and more subtle means. His duels against foes of the Empire are legendary. He strode as a god on the battlefield.
Soon, the new expanded borders were secure and peace reigned throughout the Empire. But, as in all things, it was not to last.
Hurstis saw this new, golden age quickly tarnish through corruption and decadence. He felt betrayed by the man he had helped, and not a little angry at the Emperor's ingratitude.
When a strong new leader emerged from the ranks of the Imperial Guard, Hurstis saw a chance to replace Milleus. With the help of the aging wizard, Kormac the Usurper took the Iron Throne.
I was a horrible mistake.
Where Milleus had been corrupt and lazy, Kormac was brutal and tyrannical. Rather than try to fix yet another mistake, Hurstis fled beyond the borders of the Empire, deep into the wilderness beyond the Wall. There he built a tower.
He raised it from the ancient rock, embued it with his power, and waited out his remaining years in meditation and study. But, alone, surrounded by monsters and wastelands, he went mad.
The lands around Hurstis's tower still bear the scars of his fury. Trees and rocks are twisted as if in horrible agony. The ground is cracked and scarred. The tower itself is  avoided by monster and freebooter alike. A faint cry echoes from its ancient confines. Is it the wind, or the terrible melancholy of a mad man?