diff --git a/code/game/turfs/open.dm b/code/game/turfs/open.dm
index 19589bbafc0..25bea0d7e06 100644
--- a/code/game/turfs/open.dm
+++ b/code/game/turfs/open.dm
@@ -24,6 +24,7 @@
 	icon = 'icons/turf/floors.dmi'
 	icon_state = "necro1"
 	baseturf = /turf/open/indestructible/necropolis
+	initial_gas_mix = "o2=14;n2=23;TEMP=300"
 
 /turf/open/indestructible/necropolis/New()
 	..()
diff --git a/code/game/turfs/simulated/floor/plating/asteroid.dm b/code/game/turfs/simulated/floor/plating/asteroid.dm
index 9c9b70ce5c3..451fc6aabf2 100644
--- a/code/game/turfs/simulated/floor/plating/asteroid.dm
+++ b/code/game/turfs/simulated/floor/plating/asteroid.dm
@@ -230,7 +230,7 @@
 		if(istype(tunnel))
 			// Small chance to have forks in our tunnel; otherwise dig our tunnel.
 			if(i > 3 && prob(20))
-				var/turf/open/floor/plating/asteroid/airless/cave/C = tunnel.ChangeTurf(data_having_type)
+				var/turf/open/floor/plating/asteroid/airless/cave/C = tunnel.ChangeTurf(data_having_type,FALSE,TRUE)
 				C.going_backwards = FALSE
 				C.produce_tunnel_from_data(rand(10, 15), dir)
 			else
@@ -256,7 +256,7 @@
 	SpawnFlora(T)
 
 	SpawnMonster(T)
-	T.ChangeTurf(turf_type)
+	T.ChangeTurf(turf_type,FALSE,TRUE)
 
 /turf/open/floor/plating/asteroid/airless/cave/proc/SpawnMonster(turf/T)
 	if(prob(30))
diff --git a/code/game/turfs/simulated/minerals.dm b/code/game/turfs/simulated/minerals.dm
index d04b7cf29cc..dc18e85f039 100644
--- a/code/game/turfs/simulated/minerals.dm
+++ b/code/game/turfs/simulated/minerals.dm
@@ -145,7 +145,7 @@
 
 	if (prob(mineralChance))
 		var/path = pickweight(mineralSpawnChanceList)
-		var/turf/T = ChangeTurf(path)
+		var/turf/T = ChangeTurf(path,FALSE,TRUE)
 
 		if(T && ismineralturf(T))
 			var/turf/closed/mineral/M = T
diff --git a/code/game/turfs/simulated/river.dm b/code/game/turfs/simulated/river.dm
index d5659ccb1fc..18e521b23f7 100644
--- a/code/game/turfs/simulated/river.dm
+++ b/code/game/turfs/simulated/river.dm
@@ -20,7 +20,7 @@
 			continue
 		W.connected = 1
 		var/turf/cur_turf = get_turf(W)
-		cur_turf.ChangeTurf(turf_type)
+		cur_turf.ChangeTurf(turf_type,FALSE,TRUE)
 		var/turf/target_turf = get_turf(pick(river_nodes - W))
 		if(!target_turf)
 			break
@@ -49,7 +49,7 @@
 				cur_turf = get_step(cur_turf, cur_dir)
 				continue
 			else
-				var/turf/river_turf = cur_turf.ChangeTurf(turf_type)
+				var/turf/river_turf = cur_turf.ChangeTurf(turf_type,FALSE,TRUE)
 				river_turf.Spread(25, 11, whitelist_area)
 
 	for(var/WP in river_nodes)
@@ -85,16 +85,16 @@
 
 	for(var/F in cardinal_turfs) //cardinal turfs are always changed but don't always spread
 		var/turf/T = F
-		if(!istype(T, logged_turf_type) && T.ChangeTurf(type) && prob(probability))
+		if(!istype(T, logged_turf_type) && T.ChangeTurf(type,FALSE,TRUE) && prob(probability))
 			T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
 
 	for(var/F in diagonal_turfs) //diagonal turfs only sometimes change, but will always spread if changed
 		var/turf/T = F
-		if(!istype(T, logged_turf_type) && prob(probability) && T.ChangeTurf(type))
+		if(!istype(T, logged_turf_type) && prob(probability) && T.ChangeTurf(type,FALSE,TRUE))
 			T.Spread(probability - prob_loss, prob_loss, whitelisted_area)
 		else if(ismineralturf(T))
 			var/turf/closed/mineral/M = T
-			M.ChangeTurf(M.turf_type)
+			M.ChangeTurf(M.turf_type,FALSE,TRUE)
 
 
 #undef RANDOM_UPPER_X
diff --git a/code/game/turfs/turf.dm b/code/game/turfs/turf.dm
index 979430920ba..559a25cf85e 100644
--- a/code/game/turfs/turf.dm
+++ b/code/game/turfs/turf.dm
@@ -136,7 +136,7 @@
 		qdel(L)
 
 //Creates a new turf
-/turf/proc/ChangeTurf(path, defer_change = FALSE)
+/turf/proc/ChangeTurf(path, defer_change = FALSE,ignore_air = FALSE)
 	if(!path)
 		return
 	if(!use_preloader && path == type) // Don't no-op if the map loader requires it to be reconstructed
@@ -147,11 +147,11 @@
 
 	var/turf/W = new path(src)
 	if(!defer_change)
-		W.AfterChange()
+		W.AfterChange(ignore_air)
 	W.blueprint_data = old_blueprint_data
 	return W
 
-/turf/proc/AfterChange() //called after a turf has been replaced in ChangeTurf()
+/turf/proc/AfterChange(ignore_air = FALSE) //called after a turf has been replaced in ChangeTurf()
 	levelupdate()
 	CalculateAdjacentTurfs()
 
diff --git a/code/modules/mob/living/simple_animal/hostile/mining_mobs.dm b/code/modules/mob/living/simple_animal/hostile/mining_mobs.dm
index 754543f29ef..37508393d7f 100644
--- a/code/modules/mob/living/simple_animal/hostile/mining_mobs.dm
+++ b/code/modules/mob/living/simple_animal/hostile/mining_mobs.dm
@@ -996,7 +996,7 @@
 	for(var/F in RANGE_TURFS(1, src))
 		if(ismineralturf(F))
 			var/turf/closed/mineral/M = F
-			M.ChangeTurf(M.turf_type)
+			M.ChangeTurf(M.turf_type,FALSE,TRUE)
 	gps = new /obj/item/device/gps/internal(src)
 
 /mob/living/simple_animal/hostile/spawner/lavaland/Destroy()