The Prophecy of Arcanus

Among the dangers of the Descent, people happened to encounter a creature surpassing the horror of even ancient crocodiles. It was an Arcanus—a terrible hybrid of a man and a gigantic snake.
 
At the first meeting with the monster, people rushed to attack, but the spells of the magicians bounced off its scales. Only at the cost of incredible efforts did one magician manage to break through the defense, opening the way for the blades of the warriors.
 
When the monster fell, his body was sent to the capital for study. But the main mystery of the monster turned out to be a ball clenched in his hand. The magician who dealt the fatal blow picked up the artifact and saw a terrible vision: the swamps, pulsating with life, absorbed the entire south, and then the entire Sphere, turning it into a boundless, fetid quagmire. In horror, he dropped the ball, and it sank into the abyss without a trace.
 
The magicians of Ericuria, having heard the story, reacted skeptically to the prophecy. However, since then, small detachments of sorcerers have been regularly sent to Nispad to investigate. Just in case. To be prepared if the ancient swamp really starts to expand.