Mutant

After a few seconds, Fluffy carried Aru and flew upward.

According to Emir and Dal, the mutant water buffalo had been seen near the boiling lake. Aru directed Fluffy in that direction, and it took a couple of minutes for them to reach the destination.

Soon, Aru noticed a dense cloud of steam rising from the ground. The drastic temperature difference between the air and the boiling water created this thick steam cloud. As he looked closer, he saw the cooled steam turning back into snow and falling into the lake below.

"It indeed looks circular," Aru commented. 

Around the lake, Aru could also see trees and other plants growing. However, the tree and plant didn't look like they had just sprouted. Most of them looked like they were developing for months or even years. 

"If it were a meteor impact, the nearby plants would have been decimated. So, it can't be that."