diff --git a/mods/skybox/init.lua b/mods/skybox/init.lua
index 6b7e081..3820556 100644
--- a/mods/skybox/init.lua
+++ b/mods/skybox/init.lua
@@ -37,10 +37,16 @@ local skies = {
 skybox = {}
 
 skybox.set = function(player, number)
+	if not player then
+		return
+	end
 	if number == 0 then
 		skybox.clear(player)
 	else
 		local sky = skies[number]
+		if not sky then
+			return
+		end
 		player:override_day_night_ratio(sky[3])
 		player:set_sky(sky[2], "skybox", {
 			sky[1] .. "Up.jpg",
@@ -55,6 +61,9 @@ skybox.set = function(player, number)
 end
 
 skybox.clear = function(player)
+	if not player then
+		return
+	end
 	player:override_day_night_ratio(nil)
 	player:set_sky("white", "regular")
 	player:set_clouds({