Resident Evil Director's Cut on PS1. I was fairly young and not very good at the "survival" aspect of the survival horror. I tried to kill everything I encountered and consumed copious amounts of ammo and herbs doing so. I reached a place where I had a single ink ribbon left, no ammo, health on the red, and confused on where I needed to go next. And I had to go do homework. So I used my last ribbon and saved.
I discovered next time I played that the way forward was through a tight corridor I missed filled with zombies who could now one-shot me. I tried and tried and literally was unable to get through. First time I ever learned the word "soft-locked" as my brother wheezed it out while laughing. Good times!
I also played that game by killing everything I saw; I just happened to also stumble into the fact that if you aim down while using the knife, it can one shot anything you hit. So it was easy af. lol
The regular zombies and the dogs. Not the bosses. At least, I don't remember... I saved my ammo for them, but that could have just been because I wanted to shoot them lol