Did the crash happen as you entered the castle or were you just walking around?
Oh also I made that fight a tiny bit easier and added a few iframes after being knocked back. Turns out it was already in place and I just never enabled it!
wow, that's strange! I've never experienced this one but I'm sure it's due to some spaghetti code somewhere and has nothing to do with that item, but stranger things have happened. I'll start looking now! Thanks so much!