GTA 3 --> At the time when I played it, I was rather young, and was easily frightened by the violence (go figure, considering that one of my favorite games now is God of War). Everything else was fine - carjacking, running from the cops, even doing the missions and getting into my own fights wasn't so bad. But for the life of me, I couldn't wrap my head around walking into neighborhoods and people wanting to attack me instantly. I recall specifically walking into the St. Marks zone, and some guy with an automatic would immediately wail on me. No matter what direction I came in, he'd find me. Scared the pants off of me every time. End game.