I was heading back to the map where I grind and I suddenly saw this which never happened before. I'll attach a print screen in this post. The funny thing was that I was able to hit it from the 2nd platform but it doesn't die. I realised that it could be a sudden/slight lag in the loading of the map or the mob spawn or some sort since after I changed channels and went back to the same channel, the "bug" was fixed?