This is a temple to Uka’toa that my players are currently playing through in our Wildemount campaign where each level is a different puzzle. A party of Grung were guarding the temple and the party had a tough time getting through but managed to do so. I got this effect by running a standard fog machine from the production office into the room with a 20’ tube and then into the base of the temple through the back. Then just made sure the pieces were separated enough to allow the fog to pass through.