Many bosses are really hard and have racked up a dozen kills per player.
What boss has the community labeled as a pushover that you've died an embarrassing number of times to?
Crystal Sage from DS3 has killed me at least 8 times every playthrough, but every forum I've visited has made them seem easy.
Yeah, sekiro can really throw you off if you just see it as another souls game. Parrying was the main combat mechanic when its usually worthless in every other souls game.
And God damn, parrying is so satisfying in it. Learning how to parry properly makes you feel like a fucking samurai.