Everytime I try to fight stumpy, its health bar doesn't show up, and all of it's attacks don't damage me at all. I've been attacking it nonstop for ages and it doesn't seem to die.
Henlo, I believe the health bar doesn’t show for stumpy. You can however check its hp by doing an in game command in all chat “@bosshp”. If your level is low then it might take quite a few hits to eventually kill it