im pretty sure there is a skybox as you can see water outside of the maps border

Type this into console
Should make the entity visible. Fly over to it and redo the command to hide the text.

im pretty sure its zombie survival not sandbox because its called "ZS_lens"

引用自 HamBlock：

im pretty sure its zombie survival not sandbox because its called "ZS_lens"

That doesn't matter, because sky_camera exists in both Sandbox and Zombie Survival - it's a base source entity provided by Source itself, not the gamemode
You could play this map on MelonRacer and you'd still have a skybox

thank you! global it worked