Hard choice, but I voted Hunters. Second would be the dogs, which are just too damn fast. The crimsons were kinda hard at first (and especially freaky when they all of a sudden lunge up from the ground), but they're easy to avoid because of how they attack. As in, when they finally get to you, they lunge at you so all you have to do is turn to the side, and they miss. Only time they suck is when you have no room to get around.
I thought the Chimeras were the most annoying. And I thought the spiders were the creepiest. Hunters are hard but they aren't scary whatsoever; I think the zombies are creepier.
Spiders aren't hard at all, but there was one time that I was in a hallway that went left and right, and when I aimed Jill she turned to the left so I knew there was something there and somehow I figured out it was a spider and it was up on a wall as usual. So I went to the right of the hall first to see what was there. Then I came back, camera angle changed, and HOLY **** the damn thing was right there... The one thing in the game that really scared the **** out of me.
Anyway, as for bosses, I don't think any were hard. Snake you just run away from really easily or around the bookcase when you really have to fight it; Shark you electrocute; you can avoid the Plant fight; Lisa you just give that gun to Barry, let him die while you push those boulders off the ledge and Lisa then jumps; that vampire dude wasn't hard (but the coffin and blood falling out all over the place was creepy); and even Tyrant was easy, just run around that thing and shoot at him. I got really lucky with Tyrant, too, cause I didn't know I was about to fight him so I didn't even bring my Magnum, and with my last shot of ammo I killed him.
I guess thats all not answering the question, though, because I avoided the fights on most. So I guess Lisa is the hardest if you really have to fight her, because she can jump over that middle thing. Either her or Tyrant.
Of course, this is all on easy and I haven't played through again yet.
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