diff --git a/baystation12.dme b/baystation12.dme
index 1042c11fd38..c202e8d62a2 100644
--- a/baystation12.dme
+++ b/baystation12.dme
@@ -1693,7 +1693,6 @@
 #include "code\modules\multiz\basic.dm"
 #include "code\modules\multiz\movement.dm"
 #include "code\modules\multiz\openspace.dm"
-#include "code\modules\multiz\openspace_overlay.dm"
 #include "code\modules\multiz\pipes.dm"
 #include "code\modules\multiz\structures.dm"
 #include "code\modules\multiz\turf.dm"
diff --git a/code/__defines/subsystem-priority.dm b/code/__defines/subsystem-priority.dm
index 0ee077a7922..a54ffbdb8fc 100644
--- a/code/__defines/subsystem-priority.dm
+++ b/code/__defines/subsystem-priority.dm
@@ -14,9 +14,9 @@
 #define SS_INIT_SMOOTHING           6	// Object icon smoothing. Creates overlays.
 #define SS_INIT_ICON_UPDATE         5	// Icon update queue flush. Should run before overlays.
 #define SS_INIT_OVERLAY             4	// Overlay flush.
-#define SS_INIT_OPENTURF            3	// Openturf flush. Should run after SSoverlay & SSicon_smooth so it copies the smoothed sprites. Causes lighting updates if starlight is enabled.
-#define SS_INIT_MISC                2	// Subsystems without an explicitly set initialization order start here.
-#define SS_INIT_LIGHTING            1	// Generation of lighting overlays and pre-bake.
+#define SS_INIT_MISC                3	// Subsystems without an explicitly set initialization order start here.
+#define SS_INIT_LIGHTING            2	// Generation of lighting overlays and pre-bake.
+#define SS_INIT_OPENTURF            1	// Openturf flush. Should run after SSoverlay & SSicon_smooth so it copies the smoothed sprites. Causes lighting updates if starlight is enabled.
 #define SS_INIT_LOBBY               0	// Lobby timer starts here.
 
 // Something to remember when setting priorities: SS_TICKER runs before Normal, which runs before SS_BACKGROUND.
diff --git a/code/controllers/subsystems/initialization/asteroid.dm b/code/controllers/subsystems/initialization/asteroid.dm
index 317c6a89028..5c9419e8c7b 100644
--- a/code/controllers/subsystems/initialization/asteroid.dm
+++ b/code/controllers/subsystems/initialization/asteroid.dm
@@ -6,7 +6,7 @@
 /datum/controller/subsystem/asteroid/Initialize(timeofday)
 	if(config.generate_asteroid)
 		// These values determine the specific area that the map is applied to.
-		// If you do not use the official Baycode moonbase map, you will need to change them.
+
 		// Create the chasms.
 		new /datum/random_map/automata/cave_system/chasms(null,0,0,3,255,255)
 		new /datum/random_map/automata/cave_system(null,0,0,3,255,255)
@@ -15,12 +15,9 @@
 		new /datum/random_map/automata/cave_system/chasms(null,0,0,5,255,255)
 		new /datum/random_map/automata/cave_system/high_yield(null,0,0,5,255,255)
 		new /datum/random_map/automata/cave_system/chasms/surface(null,0,0,6,255,255)
+		
 		// Create the deep mining ore distribution map.
 		new /datum/random_map/noise/ore(null, 0, 0, 5, 64, 64)
 		new /datum/random_map/noise/ore(null, 0, 0, 4, 64, 64)
 		new /datum/random_map/noise/ore(null, 0, 0, 3, 64, 64)
-		var/counting_result = "Total number of chasms: [SSopenturf.openspace_turfs.len]"
-		admin_notice(span("danger", counting_result))
-		game_log("ASGEN", counting_result)
-
 	..()
diff --git a/code/controllers/subsystems/openturf.dm b/code/controllers/subsystems/openturf.dm
index 1715bf8c5ad..87ae3c72455 100644
--- a/code/controllers/subsystems/openturf.dm
+++ b/code/controllers/subsystems/openturf.dm
@@ -97,18 +97,12 @@
 		// Handle space parallax & starlight.
 		if (T.is_above_space())
 			T.plane = PLANE_SPACE_BACKGROUND
-			if (config.starlight)
-				for (var/thing in RANGE_TURFS(1, T))
-					var/turf/RT = thing
-					if (!RT.dynamic_lighting || istype(RT, /turf/simulated/open))
-						continue
-
-					T.set_light(config.starlight, 0.5)
-					break
+			/*if (config.starlight)	// Openturf starlight is broken. SSlighting and SSopenturf will fight if this is un-commented-out. Maybe someone will fix it someday.
+				T.set_light(config.starlight, 0.5)*/
 		else
 			T.plane = OPENTURF_MAX_PLANE - depth
-			if (config.starlight && T.light_range != 0)
-				T.set_light(0)
+			/*if (config.starlight && T.light_range != 0)
+				T.set_light(0)*/
 
 		// Add everything below us to the update queue.
 		for (var/thing in T.below)
@@ -167,11 +161,10 @@
 		OO.dir = OO.associated_atom.dir
 		OO.appearance = OO.associated_atom
 		OO.plane = OPENTURF_MAX_PLANE - OO.depth
+		OO.queued = FALSE
 
-		// Something's above us, queue it.
-		var/turf/oo_loc = OO.loc
-		if (istype(oo_loc.above))
-			oo_loc.above.update_icon()
+		if (OO.bound_overlay)	// If we have a bound overlay, queue it too.
+			OO.update_oo()
 
 		if (no_mc_tick)
 			CHECK_TICK
diff --git a/code/modules/lighting/lighting_overlay.dm b/code/modules/lighting/lighting_overlay.dm
index b96e61615d8..286eb34ab89 100644
--- a/code/modules/lighting/lighting_overlay.dm
+++ b/code/modules/lighting/lighting_overlay.dm
@@ -119,6 +119,9 @@
 	)
 #endif 
 
+	if (bound_overlay)
+		update_oo()
+
 // Variety of overrides so the overlays don't get affected by weird things.
 
 /atom/movable/lighting_overlay/ex_act(severity)
diff --git a/code/modules/lighting/lighting_source.dm b/code/modules/lighting/lighting_source.dm
index d36f70ef995..3844f7cda7d 100644
--- a/code/modules/lighting/lighting_source.dm
+++ b/code/modules/lighting/lighting_source.dm
@@ -371,6 +371,7 @@
 	var/Sy = source_turf.y
 
 	FOR_DVIEW(T, Ceiling(light_range), source_turf, 0)
+		check_t:
 		if (light_angle && check_light_cone(T.x, T.y))
 			continue
 
@@ -379,6 +380,11 @@
 			corners[C] = 0
 
 		turfs += T
+
+		if (istype(T, /turf/simulated/open) && T:below)
+			T = T:below	// Consider the turf below us as well. (Z-lights)
+			goto check_t
+
 	END_FOR_DVIEW
 
 	LAZYINITLIST(affecting_turfs)
diff --git a/code/modules/multiz/openspace.dm b/code/modules/multiz/openspace.dm
index e2d09915466..ccfc2127751 100644
--- a/code/modules/multiz/openspace.dm
+++ b/code/modules/multiz/openspace.dm
@@ -49,7 +49,7 @@
 		return
 
 	// check_existence returns TRUE if the overlay is valid.
-	if (bound_overlay.check_existence())
+	if (bound_overlay.check_existence() && !bound_overlay.queued)
 		SSopenturf.queued_overlays += bound_overlay
 
 /atom/movable/proc/get_above_oo()
@@ -105,4 +105,47 @@
 
 	return ..()
 
-// /atom/movable/openspace/overlay is in openspace_overlay.dm
+// The visual representation of an atom under an openspace turf.
+/atom/movable/openspace/overlay
+	plane = OPENTURF_MAX_PLANE
+	var/atom/movable/associated_atom
+	var/depth
+	var/queued = FALSE
+
+/atom/movable/openspace/overlay/New()
+	SSopenturf.openspace_overlays += src
+
+/atom/movable/openspace/overlay/Destroy()
+	SSopenturf.openspace_overlays -= src
+
+	if (associated_atom)
+		associated_atom.bound_overlay = null
+		associated_atom = null
+
+	return ..()
+
+/atom/movable/openspace/overlay/attackby(obj/item/W, mob/user)
+	user << span("notice", "\The [src] is too far away.")
+
+/atom/movable/openspace/overlay/attack_hand(mob/user as mob)
+	user << span("notice", "You cannot reach \the [src] from here.")
+
+/atom/movable/openspace/overlay/attack_generic(mob/user as mob)
+	user << span("notice", "You cannot reach \the [src] from here.")
+
+/atom/movable/openspace/overlay/forceMove(atom/dest)
+	. = ..()
+	check_existence()
+
+/atom/movable/openspace/overlay/Move()
+	. = ..()
+	check_existence()
+
+// Checks if we've moved off of an openturf.
+// Returns TRUE if we're continuing to exist, FALSE if we're deleting ourselves.
+/atom/movable/openspace/overlay/proc/check_existence()
+	if (!istype(loc, /turf/simulated/open))
+		qdel(src)
+		return FALSE
+	else
+		return TRUE
diff --git a/code/modules/multiz/openspace_overlay.dm b/code/modules/multiz/openspace_overlay.dm
deleted file mode 100644
index abbacc12a1f..00000000000
--- a/code/modules/multiz/openspace_overlay.dm
+++ /dev/null
@@ -1,43 +0,0 @@
-// The visual representation of an atom under an openspace turf.
-/atom/movable/openspace/overlay
-	plane = OPENTURF_MAX_PLANE
-	var/atom/movable/associated_atom
-	var/depth
-
-/atom/movable/openspace/overlay/New()
-	SSopenturf.openspace_overlays += src
-
-/atom/movable/openspace/overlay/Destroy()
-	SSopenturf.openspace_overlays -= src
-
-	if (associated_atom)
-		associated_atom.bound_overlay = null
-		associated_atom = null
-
-	return ..()
-
-/atom/movable/openspace/overlay/attackby(obj/item/W, mob/user)
-	user << span("notice", "\The [src] is too far away.")
-
-/atom/movable/openspace/overlay/attack_hand(mob/user as mob)
-	user << span("notice", "You cannot reach \the [src] from here.")
-
-/atom/movable/openspace/overlay/attack_generic(mob/user as mob)
-	user << span("notice", "You cannot reach \the [src] from here.")
-
-/atom/movable/openspace/overlay/forceMove(atom/dest)
-	. = ..()
-	check_existence()
-
-/atom/movable/openspace/overlay/Move()
-	. = ..()
-	check_existence()
-
-// Checks if we've moved off of an openturf.
-// Returns TRUE if we're continuing to exist, FALSE if we're deleting ourselves.
-/atom/movable/openspace/overlay/proc/check_existence()
-	if (!istype(loc, /turf/simulated/open))
-		qdel(src)
-		return FALSE
-	else
-		return TRUE
diff --git a/html/changelogs/lohikar-zlights.yml b/html/changelogs/lohikar-zlights.yml
new file mode 100644
index 00000000000..0bf551d79be
--- /dev/null
+++ b/html/changelogs/lohikar-zlights.yml
@@ -0,0 +1,4 @@
+author: Lohikar
+delete-after: True
+changes: 
+  - tweak: "Lights will now shine through Z-holes (openturfs)."