I am currently having an issue where Biters show up as Coznix, the Fallen Beholder. His music plays and the AI and damage is the same as Coznix, but it has the health of a Biter and drops normal Biter drops. Other enemies have a similar issue. For example, a Life Crystal Mimic's AI is replaced with The Lich. When I died to it, it said I had been killed by a Life Crystal Mimic, so that's the only reason why I knew what it was supposed to be. Other enemies underground are replaced by the Druid and Diver NPCs. I'm not sure what they are supposed to be but it is funny that the Druid drops rocks on my head while I can still view her shop page. I can also interact with the Diver but he moves around like he is trying to attack me. Goblin Trappers are replaced with Gilded Slimelings. I finally realized that this was going to be troublesome for progression when the Blacksmith moved in. It wasn't the Blacksmith NPC but the Big Bones enemy from the dungeon. It did not attack me but I could attack it. When I killed it, it said the Blacksmith was slain. Like I mentioned in the title, this could be a variety of issues. I have not played the world on Singleplayer and I do have a variety of other mods installed that may be interfering, including Calamity mod and Terraria Overhaul. I think it could possibly be Terraria Overhaul mod messing with some entity IDs, but that's the only one I think could be causing the problem. I will try to see if I have any issues if I disable the mod, and I will update once I figure it out. If none of these are the problem, I can provide the full list of mods I have enabled and maybe we can pinpoint the problem. Thanks in advance.