What are some giallo films I should see?

I’m an avid horror film fan. I’ve got my favorites and ones I try to avoid. American remakes of asian films, in particular. It stopped being okay after The Ring. I’ve asked a quesiton earlier about general scary movies and I’ve gotten some really good ones to go and check out. I noticed quite a few were giallo films. I’ve only been aware of them far a very, very short while. I’ve heard the names of Bava and Argento, as well. I love the random and cultish type. So, the more obscure, the better. I really like getting recommendations and why they’re so good, so fire away.