Well, as a lot of other users already said, Akers running after you as soon as you broke the window to Brandon's body was incredibly brilliant and scary. It's really a pity that the level ends up with him spawning over and over after every two steps, forcing you to backtrack, hiding, waiting, and then repeat. Also it was really unfair to allow the player to trap him into the medical lab...and then let him return as soon as you walk one or two rooms away from it. All in all, Aker is a very good encounter that become REALLY annoying the more time you have to wait to get past him. Same thing with the other proxies in the following section. They add near to nothing to the game, and it's puzzling to see that they are so dumb when compared to Akers.
The metal brain girl was cool, but after one or two fruitless tries to get her attention and "catch" her AI, i just get bored, took the battery and immediatly run for the exit. I can't even remember if something happened or not at all. Same for the final chase. I was totally expecting it so that, as soon as i was heading back to Catherine, i just start running without even wait for the music to warn him about the danger. Again, i don't even saw what was after me.
The Disco Guy is incredibly scary and cool when you suddenly meet him during the ocean swin, but when you land on the ship and you find those rooms filled with them, things begin to get confusing. I get into a room, i saw one, and i immediatly glance elsewhere while backtracking a little. Then i try again, but the monster is still there. What to do? I try not step backwards but only to glance aside, but i'm knocked out almost immediatly. I ends up dying once or twice before just sprinting the hell away from them through those rooms, looking at them or not, which was a little letdown.
The most brilliant encounter is the guy in the space suit, mostly because it's the only enemy that you have to approach in a very fast and active way, because hiding or running is utterly useless against him (and it's terrify to run, hide, and just hear him charging straight for your spot). Again, however, the scene is somehow ruined by the fact that, the moment you realize that you just have to climb a ladder to escape, you can get past him once and then just open the red door and wait. Even if he comes again and knock you out, by that time the door is open and you can just get up and walk away. That was a pity. I would have liked more time for that sucker
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