Zyrex in the Wall World is unknown power. They are creatures that live in the fog and attack lonely travelers in groups but are afraid to invade cities because there are too many turrets.
There are several known species of Zyrex. Some can run on vertical surfaces, others can fly, but - from time to time - a previously unknown creature will appear that no one ever witnessed. There is a theory that they evolve in the wild, but this doesn't happen on the Wall. No one ever found a Zyrex nest on the Wall – most likely they live elsewhere.
Some even claim that Zyrex are divine punishment for exploring and mining the Wall.
https://store.steampowered.com/app/2187290/Wall_World/
