There's a lot of content in MMOs that's easy to get used to. You head off to the regular raid and it's not that different from punching a clock at work. The creatures that once seemed so brutish and intimidating are as familiar as household objects. Even raid bosses, designed to be impressive, can often be reduced to a mere business of choreography.
But sometimes there's content in MMOs that makes us jump out of our seats. This blogger clearly remembers the first time he encountered Circle of Thorns spectrals in a cavern, over in City of Heroes. The Circle mages themselves aren't all that intimidating: cowl-wearing flaming-eyed sorcerers, a bit like Jawas on steroids. But when you enter a mission expecting to find them and suddenly you're surrounded by unearthly shrieks and ghostly figures howling around you like the climax of Raiders of the Lost Ark, it's a shock to the system. Confronting the bat demon in Age of Conan was an adrenalin surge moment, too; that thing is big, and it appears very suddenly.
Have you ever had a frightening moment in an MMO? Did any creature make your heart rate go up the first time you encountered it? Should MMOs build in deliberate shocks and surprises? Or are you made of sterner stuff?