Conveniently, evil already has a visual language. Put another way: I have seen the face of evil, and it is a caricature of gothic construction. There’s barely a necromancer in existence whose dark citadel doesn’t in some way reflect real-world Romanian landmarks, such as Hunyad or Bran Castle. The visual theme of these games is so heavily dependent on previously pillaged artistic ideas from Dungeons & Dragons and Tolkien that evil ambiance is delivered by shorthand. (Of course, World of Warcraft’s Lich King gets a Stone UFO to fly around in — but it’s still the same old prefab pseudo-Medieval schtick inside). Where the enemy is extra-terrestrial, HR Giger’s influence is probably going to be felt instead.