The Enemy
As the others were fighting against the monsters, Reign was running with great speed toward the place where he felt faint mana undulations. The mana movement was small and hard to spot, but thanks to his incredibly high mana sensitivity, Reign was able to spot it. He made way to the enemies that were currently using the monsters in order to attack Carlo and his people while making sure that his mana was hidden and that his movement wouldn't be found out right away.
He wasn't certain if there was anyone that was watching over Carlo and the group and notifying the others, but even if there were, Reign had moved with such speed and in such chaos that it would be hard for someone below Tier I to spot him. His mana, his presence, and his body were well hidden by the items he was still carrying on his body as he made his way to the place he felt mana coming from.