Destroyer Glitch - Not sure what mod

[Oliverrook]

So, I've recently been trying to defeat the Destroyer in Hardmode, but noticed that whenever it spawns, 90%+ of its segments are immediately destroyed, but none of its health goes with it, making it incredibly difficult to hit and almost impossible to beat in just one night, as it still burrows into the ground for a long time, and only a very small part of it can actually be hit.
Does anybody know what mod is causing this? Some help would be greatly appreciated.