Lin Mu had felt the spatial energy fluctuations which were the biggest sign that a teleportation portal had opened. And there was only one reason why there would be a teleportation portal in the Land of Exile.
Someone had just been exiled.
Lin Mu's eyes darted around and his spirit sense was extended as well. Even if its range was limited, he would at least detect any attacks within that range and be able to react to it.
"There!" Head Warrior Kulo was the first to spot the portal.
He was a lot more experienced in this and had seen several portals open in the past. Lin Mu too noticed it, and saw that the runes were very faint and hard to read.
'They've been hidden intentionally…' Lin Mu discovered.
It was possibly made with caution against Formation masters tampering with it, so they simply kept the runes hidden. Doing this for a large and complex array like this was very difficult as well as expensive.