The role of fog, haze, and perfectly timed effects in theme park Halloween scares is a crucial part of the experience for Halloween Horror Nights. The fog, or "fog," is a mix of fog and haze, which often occur at the same time as audio and lighting. Most larger attractions use DMX control systems, the same technology used for stage lighting, and more advanced systems where multiple elements are layered together. Special effects company SurgeFX, based in Ohio, explained that fog effects are treated just like any other show element and timed alongside audio, lighting. The company highlighted that fog is used in short bursts for big scares, while haze is a fine, lingering mist that hangs in the air.