Silent Hill's fog was famously inspired by a hardware limitation. The short draw-distance of the original PlayStation, combined with a fondness for Stephen King's The Mist, led to a town covered in clouds of fog that hid distant detail. This handily masked the limitation, but also meant that you heard monsters before you saw them—footsteps or wingbeats suggesting their presence before they appeared. The designers leant into this, adding a radio that buzzed with static when the reality-defying monsters were close, and cementing a formula for effective dread that carried over multiple sequels...
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Silent Hill 2 players are modding away the fog and freeing the camera to discover hidden detail in the remake
Source: PC Gamer (opens in a new tab)