Mordruuk is somewhere nearby

When Kagrohan found out that Aldrik's students not only survived, but were also rushing to the sealed observatory, his rage knew no bounds. He couldn't let the magic of the Abyss break free.
 
To finally bury Aldrik's legacy, the First Demon strengthened the observatory's defenses. To do this, he ordered the creation of a three-headed dog Mordruuk. The creature knew no pity and fatigue. For centuries, it stood on guard and attacked anyone who dared to approach the forbidden place.
 
Over time, the Abyss began to seep through the cracks in the seal that was superimposed on the observatory. And the first one she touched was Mordruuk. Magic was ingrained in his mind, distorted his very essence. The Great guardian ceased to be a servant of Kagrohan, he began to obey the Abyss and left his post. Shamans tried to track him down, but the tracks stopped, as if magic was hiding the fugitive.
 
Centuries have passed, but the demons remember this creature and are afraid that one day he will return. And his intentions will obviously be unkind.