Frankenstein, Dracula, Werewolf, Freddy Krueger, Jason Voorhees, Michael Myers, Chucky, Ghostface (OK, he's not a single killer bur rather a disguise for several different ones, but still), Jigsaw, etc. There's other lesser known ones, such as The Leprechaun (Leprechaun series), The Tall Man (Phantasm series), Matt Cordell (Maniac Cop series), Angela/Peter Baker (Sleepaway Camp movies), Candyman (Candyman series), etc. Which series and killer do you find the most entertaining? My pick is Freddy. He's got the best backstory, the most imaginative way of killing people (in their dreams + his way of purposefully toying with his victims and using their personal desires/fears against them before offing them), and a lot of personality and charisma to boot.