6. Sander Cohen (Bioshock)
For me, Sander Cohen is probably the creepiest person on this list. If I was asked about my favorite memory of the first Bioshock, my time spent with this groundbreaking character would be first and fore-most. The first thing that stands out to me is that he is the first openly gay character in a game I've seen much less a villain, and that is something I love. He is an artist in every sense of the word, and more than anything it shows that evil can take the form of anything, and all it takes is one bad day. What makes this character unforgettable is the task he makes you complete: after locking you in an area and blocking all radio communication, the man sends you on a quest for blood, making you kill all of his former disciples that abandoned or betrayed him. The sick part is that he makes you take a picture of their dead body so it can be added to a piece of "art" that he is working on. The point where it gets tough is when all of them are killed and you meet Cohen face to face. Throughout the level the man even rewards you and gives you tools to help you through the mission. When it gets to the end and you have the option of fighting and killing him, it's almost hard to because you feel sorry for the man and he never actually did anything wrong to you. For me, it was an easy choice: I killed him - the locked up chest was so enticing that I really wanted to know what was inside. But still, an unforgettable villain.