diff --git a/code/game/turfs/turf.dm b/code/game/turfs/turf.dm
index 8db23214265..26bd4c697ae 100644
--- a/code/game/turfs/turf.dm
+++ b/code/game/turfs/turf.dm
@@ -178,7 +178,7 @@ var/const/enterloopsanity = 100
 	if(!(A.last_move))	return
 	if((istype(A, /mob/) && src.x > 2 && src.x < (world.maxx - 1) && src.y > 2 && src.y < (world.maxy-1)))
 		var/mob/M = A
-		if(M.Process_Spacemove(1))
+		if(M.Allow_Spacemove(1))
 			M.inertia_dir  = 0
 			return
 		spawn(5)
diff --git a/code/game/turfs/turf_changing.dm b/code/game/turfs/turf_changing.dm
index 04adf11fb94..8797e040811 100644
--- a/code/game/turfs/turf_changing.dm
+++ b/code/game/turfs/turf_changing.dm
@@ -8,6 +8,12 @@
 	var/obj/structure/lattice/L = locate(/obj/structure/lattice, src)
 	if(L)
 		qdel(L)
+// Called after turf replaces old one
+/turf/proc/post_change()
+	levelupdate()
+	var/turf/simulated/open/T = GetAbove(src)
+	if(istype(T))
+		T.update_icon()
 
 //Creates a new turf
 /turf/proc/ChangeTurf(var/turf/N, var/tell_universe=1, var/force_lighting_update = 0)
@@ -17,8 +23,8 @@
 	// This makes sure that turfs are not changed to space when one side is part of a zone
 	if(N == /turf/space)
 		var/turf/below = GetBelow(src)
-		if(istype(below) && (air_master.has_valid_zone(below) || air_master.has_valid_zone(src)))
-			N = /turf/simulated/open
+		if(istype(below) && !istype(below,/turf/space))
+			N = below.density ? /turf/simulated/floor/airless : /turf/simulated/open
 
 	var/obj/fire/old_fire = fire
 	var/old_opacity = opacity
@@ -27,10 +33,13 @@
 	var/old_lighting_overlay = lighting_overlay
 	var/list/old_corners = corners
 
-	//world << "Replacing [src.type] with [N]"
+//	log_debug("Replacing [src.type] with [N]")
+
 
 	if(connections) connections.erase_all()
 
+	overlays.Cut()
+	underlays.Cut()
 	if(istype(src,/turf/simulated))
 		//Yeah, we're just going to rebuild the whole thing.
 		//Despite this being called a bunch during explosions,
@@ -38,44 +47,27 @@
 		var/turf/simulated/S = src
 		if(S.zone) S.zone.rebuild()
 
-	if(ispath(N, /turf/simulated/floor))
-		var/turf/simulated/W = new N( locate(src.x, src.y, src.z) )
+	var/turf/simulated/W = new N( locate(src.x, src.y, src.z) )
+
+	if(ispath(N, /turf/simulated))
 		if(old_fire)
 			fire = old_fire
-
 		if (istype(W,/turf/simulated/floor))
 			W.RemoveLattice()
+	else if(old_fire)
+		old_fire.RemoveFire()
 
-		if(tell_universe)
-			universe.OnTurfChange(W)
+	if(tell_universe)
+		universe.OnTurfChange(W)
 
-		if(air_master)
-			air_master.mark_for_update(src) //handle the addition of the new turf.
+	if(air_master)
+		air_master.mark_for_update(src) //handle the addition of the new turf.
 
-		for(var/turf/space/S in range(W,1))
-			S.update_starlight()
+	for(var/turf/space/S in range(W,1))
+		S.update_starlight()
 
-		W.levelupdate()
-		. = W
-
-	else
-
-		var/turf/W = new N( locate(src.x, src.y, src.z) )
-
-		if(old_fire)
-			old_fire.RemoveFire()
-
-		if(tell_universe)
-			universe.OnTurfChange(W)
-
-		if(air_master)
-			air_master.mark_for_update(src)
-
-		for(var/turf/space/S in range(W,1))
-			S.update_starlight()
-
-		W.levelupdate()
-		. =  W
+	W.post_change()
+	. = W
 
 	lighting_overlay = old_lighting_overlay
 	affecting_lights = old_affecting_lights
@@ -87,3 +79,26 @@
 			lighting_build_overlay()
 		else
 			lighting_clear_overlay()
+
+/turf/proc/transport_properties_from(turf/other)
+	if(!istype(other, src.type))
+		return 0
+
+	src.set_dir(other.dir)
+	src.icon_state = other.icon_state
+	src.icon = other.icon
+	src.overlays = other.overlays.Copy()
+	src.underlays = other.underlays.Copy()
+	return 1
+
+//I would name this copy_from() but we remove the other turf from their air zone for some reason
+/turf/simulated/transport_properties_from(turf/simulated/other)
+	if(!..())
+		return 0
+
+	if(other.zone)
+		if(!src.air)
+			src.make_air()
+		src.air.copy_from(other.zone.air)
+		other.zone.remove(other)
+	return 1
diff --git a/code/modules/clothing/spacesuits/rig/rig.dm b/code/modules/clothing/spacesuits/rig/rig.dm
index 07efb35d114..4ebdd5de1b1 100644
--- a/code/modules/clothing/spacesuits/rig/rig.dm
+++ b/code/modules/clothing/spacesuits/rig/rig.dm
@@ -846,9 +846,14 @@
 	if(!wearer.lastarea)
 		wearer.lastarea = get_area(wearer.loc)
 
-	if((istype(wearer.loc, /turf/space)) || (wearer.lastarea.has_gravity == 0))
-		if(!wearer.Process_Spacemove(0))
+	if(!wearer.check_solid_ground())
+		var/allowmove = wearer.Allow_Spacemove(0)
+		if(!allowmove)
 			return 0
+		else if(allowmove == -1 && wearer.handle_spaceslipping()) //Check to see if we slipped
+			return 0
+		else
+			wearer.inertia_dir = 0 //If not then we can reset inertia and move
 
 	if(malfunctioning)
 		direction = pick(cardinal)
diff --git a/code/modules/mob/living/carbon/human/human_movement.dm b/code/modules/mob/living/carbon/human/human_movement.dm
index a3f1fa409d2..254e729c773 100644
--- a/code/modules/mob/living/carbon/human/human_movement.dm
+++ b/code/modules/mob/living/carbon/human/human_movement.dm
@@ -75,7 +75,7 @@
 
 
 
-/mob/living/carbon/human/Process_Spacemove(var/check_drift = 0)
+/mob/living/carbon/human/Allow_Spacemove(var/check_drift = 0)
 	//Can we act?
 	if(restrained())	return 0
 
@@ -89,9 +89,6 @@
 			for(var/obj/item/rig_module/maneuvering_jets/module in rig.installed_modules)
 				thrust = module.jets
 				break
-		else if(istype(back,/obj/item/weapon/storage/backpack/typec))
-			inertia_dir = 0
-			return 1
 
 	if(thrust)
 		if(((!check_drift) || (check_drift && thrust.stabilization_on)) && (!lying) && (thrust.allow_thrust(0.01, src)))
@@ -99,9 +96,7 @@
 			return 1
 
 	//If no working jetpack then use the other checks
-	if(..())
-		return 1
-	return 0
+	. = ..()
 
 
 /mob/living/carbon/human/slip_chance(var/prob_slip = 5)
diff --git a/code/modules/mob/living/carbon/metroid/metroid.dm b/code/modules/mob/living/carbon/metroid/metroid.dm
index 99ffce0eebb..2494f00f1e8 100644
--- a/code/modules/mob/living/carbon/metroid/metroid.dm
+++ b/code/modules/mob/living/carbon/metroid/metroid.dm
@@ -140,8 +140,8 @@
 
 	..()
 
-/mob/living/carbon/slime/Process_Spacemove()
-	return 2
+/mob/living/carbon/slime/Allow_Spacemove()
+	return 1
 
 /mob/living/carbon/slime/Stat()
 	..()
@@ -381,4 +381,4 @@
 		if(powerlevel > 10)
 			powerlevel = 10
 			adjustToxLoss(-10)
-	nutrition = max(nutrition, get_max_nutrition())
\ No newline at end of file
+	nutrition = max(nutrition, get_max_nutrition())
diff --git a/code/modules/mob/living/silicon/robot/robot_movement.dm b/code/modules/mob/living/silicon/robot/robot_movement.dm
index 5897fc6624f..b4c1414f7d9 100644
--- a/code/modules/mob/living/silicon/robot/robot_movement.dm
+++ b/code/modules/mob/living/silicon/robot/robot_movement.dm
@@ -3,23 +3,12 @@
 		return 0
 	..(prob_slip)
 
-/mob/living/silicon/robot/Process_Spacemove(var/check_drift = 0)//Cleaned up, fixed and simplified this function
-	//If checkdrift is 0, we're checking to see if we can manually move, return true if jetpack is on
-	//if checkdrift is 1, we're checking to see if we drift. Return true if jetpack AND stabilisers are on
-	if(jetpack)
-		//var/obj/item/weapon/tank/jetpack/J = internals
-
-		if (check_drift)
-			if (jetpack.stabilization_on && jetpack.allow_thrust(0.01))
-				inertia_dir = 0
+/mob/living/silicon/robot/Allow_Spacemove()
+	if(module)
+		for(var/obj/item/weapon/tank/jetpack/J in module.modules)
+			if(J && J.allow_thrust(0.01))
 				return 1
-
-		else if(jetpack.allow_thrust(0.01))
-			inertia_dir = 0
-			return 1
-	if(..())//The parent function checks for nearby objects to hold onto
-		return 1
-	return 0
+	. = ..()
 
  //No longer needed, but I'll leave it here incase we plan to re-use it.
 /mob/living/silicon/robot/movement_delay()
@@ -42,4 +31,4 @@
 		return 0
 
 	if (cell_use_power(actuatorComponent.active_usage))
-		return ..()
\ No newline at end of file
+		return ..()
diff --git a/code/modules/mob/living/simple_animal/hostile/bat.dm b/code/modules/mob/living/simple_animal/hostile/bat.dm
index 6beb094c944..e42bc13d04f 100644
--- a/code/modules/mob/living/simple_animal/hostile/bat.dm
+++ b/code/modules/mob/living/simple_animal/hostile/bat.dm
@@ -44,7 +44,7 @@
 	if(istype(L))
 		owner = L
 
-/mob/living/simple_animal/hostile/scarybat/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/scarybat/Allow_Spacemove(var/check_drift = 0)
 	return ..()	//No drifting in space for space carp!	//original comments do not steal
 
 /mob/living/simple_animal/hostile/scarybat/FindTarget()
diff --git a/code/modules/mob/living/simple_animal/hostile/bear.dm b/code/modules/mob/living/simple_animal/hostile/bear.dm
index a7ce2464778..4fb011c7e29 100644
--- a/code/modules/mob/living/simple_animal/hostile/bear.dm
+++ b/code/modules/mob/living/simple_animal/hostile/bear.dm
@@ -304,7 +304,7 @@
 			instant_aggro()
 
 
-/mob/living/simple_animal/hostile/bear/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/bear/Allow_Spacemove(var/check_drift = 0)
 	inertia_dir = 0
 	return 1	//No drifting in space for space bears!
 	//Fixed this, it wasnt working
diff --git a/code/modules/mob/living/simple_animal/hostile/carp.dm b/code/modules/mob/living/simple_animal/hostile/carp.dm
index a3e2724e13c..cca64d099d8 100644
--- a/code/modules/mob/living/simple_animal/hostile/carp.dm
+++ b/code/modules/mob/living/simple_animal/hostile/carp.dm
@@ -39,7 +39,7 @@
 
 	faction = "carp"
 
-/mob/living/simple_animal/hostile/carp/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/carp/Allow_Spacemove(var/check_drift = 0)
 	return 1	//No drifting in space for space carp!	//original comments do not steal
 
 /mob/living/simple_animal/hostile/carp/FindTarget()
@@ -68,4 +68,4 @@
 /mob/living/simple_animal/hostile/carp/russian/FindTarget()
     . = ..()
     if(.)
-        custom_emote(1,"spots a filthy capitalist!")
\ No newline at end of file
+        custom_emote(1,"spots a filthy capitalist!")
diff --git a/code/modules/mob/living/simple_animal/hostile/faithless.dm b/code/modules/mob/living/simple_animal/hostile/faithless.dm
index 44d9c5d1ac4..417be0aa131 100644
--- a/code/modules/mob/living/simple_animal/hostile/faithless.dm
+++ b/code/modules/mob/living/simple_animal/hostile/faithless.dm
@@ -32,7 +32,7 @@
 
 	faction = "faithless"
 
-/mob/living/simple_animal/hostile/faithless/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/faithless/Allow_Spacemove(var/check_drift = 0)
 	return 1
 
 /mob/living/simple_animal/hostile/faithless/FindTarget()
diff --git a/code/modules/mob/living/simple_animal/hostile/retaliate/cavern.dm b/code/modules/mob/living/simple_animal/hostile/retaliate/cavern.dm
index b4b21e02bcb..054daafeabc 100644
--- a/code/modules/mob/living/simple_animal/hostile/retaliate/cavern.dm
+++ b/code/modules/mob/living/simple_animal/hostile/retaliate/cavern.dm
@@ -36,7 +36,7 @@
 
 	faction = "cavern"
 
-/mob/living/simple_animal/hostile/retaliate/cavern_dweller/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/retaliate/cavern_dweller/Allow_Spacemove(var/check_drift = 0)
 	return 1
 
 /obj/item/projectile/beam/cavern
diff --git a/code/modules/mob/living/simple_animal/hostile/retaliate/drone.dm b/code/modules/mob/living/simple_animal/hostile/retaliate/drone.dm
index b8e4bb63bc6..6bf45c5f234 100644
--- a/code/modules/mob/living/simple_animal/hostile/retaliate/drone.dm
+++ b/code/modules/mob/living/simple_animal/hostile/retaliate/drone.dm
@@ -58,7 +58,7 @@
 	ion_trail.set_up(src)
 	ion_trail.start()
 
-/mob/living/simple_animal/hostile/retaliate/malf_drone/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/retaliate/malf_drone/Allow_Spacemove(var/check_drift = 0)
 	return 1
 
 /mob/living/simple_animal/hostile/retaliate/malf_drone/ListTargets()
diff --git a/code/modules/mob/living/simple_animal/hostile/syndicate.dm b/code/modules/mob/living/simple_animal/hostile/syndicate.dm
index 7f240e8a21e..524f89d0515 100644
--- a/code/modules/mob/living/simple_animal/hostile/syndicate.dm
+++ b/code/modules/mob/living/simple_animal/hostile/syndicate.dm
@@ -99,7 +99,7 @@
 	corpse = /obj/effect/landmark/mobcorpse/syndicatecommando
 	speed = 0
 
-/mob/living/simple_animal/hostile/syndicate/melee/space/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/syndicate/melee/space/Allow_Spacemove(var/check_drift = 0)
 	return
 
 /mob/living/simple_animal/hostile/syndicate/ranged
@@ -129,7 +129,7 @@
 	corpse = /obj/effect/landmark/mobcorpse/syndicatecommando
 	speed = 0
 
-/mob/living/simple_animal/hostile/syndicate/ranged/space/Process_Spacemove(var/check_drift = 0)
+/mob/living/simple_animal/hostile/syndicate/ranged/space/Allow_Spacemove(var/check_drift = 0)
 	return
 
 
diff --git a/code/modules/mob/mob_movement.dm b/code/modules/mob/mob_movement.dm
index acd83da6644..a282a861421 100644
--- a/code/modules/mob/mob_movement.dm
+++ b/code/modules/mob/mob_movement.dm
@@ -244,8 +244,14 @@
 	if(!mob.lastarea)
 		mob.lastarea = get_area(mob.loc)
 
-	if((istype(mob.loc, /turf/space)) || (mob.lastarea.has_gravity == 0))
-		if(!mob.Process_Spacemove(0))	return 0
+	if(!mob.check_solid_ground())
+		var/allowmove = mob.Allow_Spacemove(0)
+		if(!allowmove)
+			return 0
+		else if(allowmove == -1 && mob.handle_spaceslipping()) //Check to see if we slipped
+			return 0
+		else
+			mob.inertia_dir = 0 //If not then we can reset inertia and move
 
 	if(isobj(mob.loc) || ismob(mob.loc))//Inside an object, tell it we moved
 		var/atom/O = mob.loc
@@ -460,31 +466,33 @@
 /mob/proc/Post_Incorpmove()
 	return
 
-///Process_Spacemove
-///Called by /client/Move()
-///For moving in space
-///Return 1 for movement 0 for none
-/mob/proc/Process_Spacemove(var/check_drift = 0)
-
+// Checks whether this mob is allowed to move in space
+// Return 1 for movement, 0 for none,
+// -1 to allow movement but with a chance of slipping
+/mob/proc/Allow_Spacemove(var/check_drift = 0)
 	if(!Check_Dense_Object()) //Nothing to push off of so end here
-		update_floating(0)
 		return 0
 
-	update_floating(1)
-
 	if(restrained()) //Check to see if we can do things
 		return 0
 
-	//Check to see if we slipped
-	if(prob(slip_chance(5)) && !buckled)
-		src << "<span class='warning'>You slipped!</span>"
-		src.inertia_dir = src.last_move
-		step(src, src.inertia_dir)
+	return -1
+
+//Checks if a mob has solid ground to stand on
+//If there's no gravity then there's no up or down so naturally you can't stand on anything.
+//For the same reason lattices in space don't count - those are things you grip, presumably.
+/mob/proc/check_solid_ground()
+	if(istype(loc, /turf/space))
 		return 0
-	//If not then we can reset inertia and move
-	inertia_dir = 0
+
+	if(!lastarea)
+		lastarea = get_area(loc)
+	if(!lastarea.has_gravity)
+		return 0
+
 	return 1
 
+
 /mob/proc/Check_Dense_Object() //checks for anything to push off in the vicinity. also handles magboots on gravity-less floors tiles
 
 	var/shoegrip = Check_Shoegrip()
@@ -514,3 +522,12 @@
 	if(Check_Shoegrip())
 		return 0
 	return prob_slip
+
+//return 1 if slipped, 0 otherwise
+/mob/proc/handle_spaceslipping()
+	if(prob(slip_chance(5)) && !buckled)
+		to_chat(src, "<span class='warning'>You slipped!</span>")
+		src.inertia_dir = src.last_move
+		step(src, src.inertia_dir)
+		return 1
+	return 0
diff --git a/code/modules/multiz/basic.dm b/code/modules/multiz/basic.dm
index e76c6516aa7..0ed4e5364a5 100644
--- a/code/modules/multiz/basic.dm
+++ b/code/modules/multiz/basic.dm
@@ -11,25 +11,43 @@ var/z_levels = 0 // Each bit represents a connection between adjacent levels.  S
 	qdel(src)
 
 // The storage of connections between adjacent levels means some bitwise magic is needed.
-proc/HasAbove(var/z)
+/proc/HasAbove(var/z)
 	if(z >= world.maxz || z > 16 || z < 1)
 		return 0
 	return z_levels & (1 << (z - 1))
 
-proc/HasBelow(var/z)
+/proc/HasBelow(var/z)
 	if(z > world.maxz || z > 17 || z < 2)
 		return 0
 	return z_levels & (1 << (z - 2))
 
 // Thankfully, no bitwise magic is needed here.
-proc/GetAbove(var/atom/atom)
+/proc/GetAbove(var/atom/atom)
 	var/turf/turf = get_turf(atom)
 	if(!turf)
 		return null
 	return HasAbove(turf.z) ? get_step(turf, UP) : null
 
-proc/GetBelow(var/atom/atom)
+/proc/GetBelow(var/atom/atom)
 	var/turf/turf = get_turf(atom)
 	if(!turf)
 		return null
 	return HasBelow(turf.z) ? get_step(turf, DOWN) : null
+
+/proc/GetConnectedZlevels(z)
+	. = list(z)
+	for(var/level = z, HasBelow(level), level--)
+		. |= level-1
+	for(var/level = z, HasAbove(level), level++)
+		. |= level+1
+
+proc/AreConnectedZLevels(var/zA, var/zB)
+	return zA == zB || (zB in GetConnectedZlevels(zA))
+
+/proc/get_zstep(ref, dir)
+	if(dir == UP)
+		. = GetAbove(ref)
+	else if (dir == DOWN)
+		. = GetBelow(ref)
+	else
+		. = get_step(ref, dir)
\ No newline at end of file
diff --git a/code/modules/multiz/movement.dm b/code/modules/multiz/movement.dm
index dd0a93fec11..98f3c17d123 100644
--- a/code/modules/multiz/movement.dm
+++ b/code/modules/multiz/movement.dm
@@ -1,51 +1,172 @@
-/obj/item/weapon/tank/jetpack/verb/moveup()
+/mob/verb/up()
 	set name = "Move Upwards"
-	set category = "Object"
+	set category = "IC"
 
-	. = 1
-	if(!allow_thrust(0.01, usr))
-		usr << "<span class='warning'>\The [src] is disabled.</span>"
+	if(zMove(UP))
+		to_chat(usr, "<span class='notice'>You move upwards.</span>")
+
+/mob/verb/down()
+	set name = "Move Down"
+	set category = "IC"
+
+	if(zMove(DOWN))
+		to_chat(usr, "<span class='notice'>You move down.</span>")
+
+/mob/proc/zMove(direction)
+	if(eyeobj)
+		return eyeobj.zMove(direction)
+	if(!can_ztravel())
+		to_chat(usr, "<span class='warning'>You lack means of travel in that direction.</span>")
 		return
 
-	var/turf/above = GetAbove(src)
-	if(!istype(above))
-		usr << "<span class='notice'>There is nothing of interest in this direction.</span>"
-		return
+	var/turf/destination = (direction == UP) ? GetAbove(src) : GetBelow(src)
 
-	if(!istype(above, /turf/space) && !istype(above, /turf/simulated/open))
-		usr << "<span class='warning'>You bump against \the [above].</span>"
-		return
+	if(!destination)
+		to_chat(usr, "<span class='notice'>There is nothing of interest in this direction.</span>")
+		return 0
 
-	for(var/atom/A in above)
-		if(A.density)
-			usr << "<span class='warning'>\The [A] blocks you.</span>"
-			return
+	var/turf/start = get_turf(src)
+	if(!start.CanZPass(src, direction))
+		to_chat(usr, "<span class='warning'>\The [start] is in the way.</span>")
+		return 0
+	if(!destination.CanZPass(src, direction))
+		to_chat(usr, "<span class='warning'>You bump against \the [destination].</span>")
+		return 0
 
-	usr.Move(above)
-	usr << "<span class='notice'>You move upwards.</span>"
+	var/area/area = get_area(src)
+	if(direction == UP && area.has_gravity)
+		to_chat(usr, "<span class='warning'>Gravity stops you from moving upward.</span>")
+		return 0
 
-/obj/item/weapon/tank/jetpack/verb/movedown()
-	set name = "Move Downwards"
-	set category = "Object"
+	for(var/atom/A in destination)
+		if(!A.CanPass(src, start, 1.5, 0))
+			to_chat(usr, "<span class='warning'>\The [A] blocks you.</span>")
+			return 0
+	Move(destination)
+	return 1
 
-	. = 1
-	if(!allow_thrust(0.01, usr))
-		usr << "<span class='warning'>\The [src] is disabled.</span>"
+/mob/eye/zMove(direction)
+	var/turf/destination = (direction == UP) ? GetAbove(src) : GetBelow(src)
+	if(destination)
+		forceMove(destination)
+	else
+		to_chat(usr, "<span class='notice'>There is nothing of interest in this direction.</span>")
+
+/mob/eye/zMove(direction)
+	var/turf/destination = (direction == UP) ? GetAbove(src) : GetBelow(src)
+	if(destination)
+		setLoc(destination)
+	else
+		to_chat(usr, "<span class='notice'>There is nothing of interest in this direction.</span>")
+
+/mob/proc/can_ztravel()
+	return 0
+
+/mob/observer/can_ztravel()
+	return 1
+
+/mob/living/carbon/human/can_ztravel()
+	if(incapacitated())
+		return 0
+
+	if(Allow_Spacemove())
+		return 1
+
+	if(Check_Shoegrip())	//scaling hull with magboots
+		for(var/turf/simulated/T in trange(1,src))
+			if(T.density)
+				return 1
+
+/mob/living/silicon/robot/can_ztravel()
+	if(incapacitated() || is_dead())
+		return 0
+
+	if(Allow_Spacemove()) //Checks for active jetpack
+		return 1
+
+	for(var/turf/simulated/T in trange(1,src)) //Robots get "magboots"
+		if(T.density)
+			return 1
+
+//FALLING STUFF
+
+//Holds fall checks that should not be overriden by children
+/atom/movable/proc/fall()
+	if(!isturf(loc))
 		return
 
 	var/turf/below = GetBelow(src)
-	if(!istype(below))
-		usr << "<span class='notice'>There is nothing of interest in this direction.</span>"
+	if(!below)
 		return
 
-	if(below.density)
-		usr << "<span class='warning'>You bump against \the [below].</span>"
+	var/turf/T = loc
+	if(!T.CanZPass(src, DOWN) || !below.CanZPass(src, DOWN))
 		return
 
+	// No gravity in space, apparently.
+	var/area/area = get_area(src)
+	if(!area.has_gravity())
+		return
+
+	if(throwing)
+		return
+
+	if(can_fall())
+		handle_fall(below)
+
+//For children to override
+/atom/movable/proc/can_fall()
+	if(anchored)
+		return FALSE
+
+	if(locate(/obj/structure/lattice, loc))
+		return FALSE
+
+	// See if something prevents us from falling.
+	var/turf/below = GetBelow(src)
 	for(var/atom/A in below)
-		if(A.density)
-			usr << "<span class='warning'>\The [A] blocks you.</span>"
-			return
+		if(!A.CanPass(src, src.loc))
+			return FALSE
 
-	usr.Move(below)
-	usr << "<span class='notice'>You move downwards.</span>"
+	return TRUE
+
+/obj/effect/can_fall()
+	return FALSE
+
+/obj/effect/decal/cleanable/can_fall()
+	return TRUE
+
+/obj/item/pipe/can_fall()
+	var/turf/simulated/open/below = loc
+	below = below.below
+
+	. = ..()
+
+	if(anchored)
+		return FALSE
+
+	if((locate(/obj/structure/disposalpipe/up) in below) || locate(/obj/machinery/atmospherics/pipe/zpipe/up in below))
+		return FALSE
+
+/atom/movable/proc/handle_fall(var/turf/landing)
+	Move(landing)
+	if(locate(/obj/structure/stairs) in landing)
+		return 1
+
+	if(istype(landing, /turf/simulated/open))
+		visible_message("\The [src] falls from the deck above through \the [landing]!", "You hear a whoosh of displaced air.")
+	else
+		visible_message("\The [src] falls from the deck above and slams into \the [landing]!", "You hear something slam into the deck.")
+
+/mob/living/carbon/human/handle_fall(var/turf/landing)
+	if(..())
+		return
+	var/damage = 10
+	apply_damage(rand(0, damage), BRUTE, "head")
+	apply_damage(rand(0, damage), BRUTE, "chest")
+	apply_damage(rand(0, damage), BRUTE, "l_leg")
+	apply_damage(rand(0, damage), BRUTE, "r_leg")
+	apply_damage(rand(0, damage), BRUTE, "l_arm")
+	apply_damage(rand(0, damage), BRUTE, "r_arm")
+	weakened = max(weakened,2)
+	updatehealth()
diff --git a/code/modules/multiz/pipes.dm b/code/modules/multiz/pipes.dm
index 1cb5b9b4da7..155ef0a7430 100644
--- a/code/modules/multiz/pipes.dm
+++ b/code/modules/multiz/pipes.dm
@@ -192,7 +192,6 @@ obj/machinery/atmospherics/pipe/zpipe/up/scrubbers
 	name = "upwards scrubbers pipe"
 	desc = "A scrubbers pipe segment to connect upwards."
 	connect_types = CONNECT_TYPE_SCRUBBER
-	layer = 2.38
 	icon_connect_type = "-scrubbers"
 	color = PIPE_COLOR_RED
 
@@ -201,7 +200,6 @@ obj/machinery/atmospherics/pipe/zpipe/up/supply
 	name = "upwards supply pipe"
 	desc = "A supply pipe segment to connect upwards."
 	connect_types = CONNECT_TYPE_SUPPLY
-	layer = 2.39
 	icon_connect_type = "-supply"
 	color = PIPE_COLOR_BLUE
 
@@ -210,7 +208,6 @@ obj/machinery/atmospherics/pipe/zpipe/down/scrubbers
 	name = "downwards scrubbers pipe"
 	desc = "A scrubbers pipe segment to connect downwards."
 	connect_types = CONNECT_TYPE_SCRUBBER
-	layer = 2.38
 	icon_connect_type = "-scrubbers"
 	color = PIPE_COLOR_RED
 
@@ -219,6 +216,16 @@ obj/machinery/atmospherics/pipe/zpipe/down/supply
 	name = "downwards supply pipe"
 	desc = "A supply pipe segment to connect downwards."
 	connect_types = CONNECT_TYPE_SUPPLY
-	layer = 2.39
 	icon_connect_type = "-supply"
 	color = PIPE_COLOR_BLUE
+
+// Colored misc. pipes
+obj/machinery/atmospherics/pipe/zpipe/up/cyan
+	color = PIPE_COLOR_CYAN
+obj/machinery/atmospherics/pipe/zpipe/down/cyan
+	color = PIPE_COLOR_CYAN
+
+obj/machinery/atmospherics/pipe/zpipe/up/red
+	color = PIPE_COLOR_RED
+obj/machinery/atmospherics/pipe/zpipe/down/red
+	color = PIPE_COLOR_RED
diff --git a/code/modules/multiz/structures.dm b/code/modules/multiz/structures.dm
index 36a606bfcf9..62edc2d7689 100644
--- a/code/modules/multiz/structures.dm
+++ b/code/modules/multiz/structures.dm
@@ -4,54 +4,123 @@
 
 /obj/structure/ladder
 	name = "ladder"
-	desc = "A ladder.  You can climb it up and down."
-	icon_state = "ladderdown"
+	desc = "A ladder. You can climb it up and down."
+	icon_state = "ladder01"
 	icon = 'icons/obj/structures.dmi'
 	density = 0
 	opacity = 0
 	anchored = 1
 
-	var/obj/structure/ladder/target
+	var/allowed_directions = DOWN
+	var/obj/structure/ladder/target_up
+	var/obj/structure/ladder/target_down
 
-	initialize()
-		// the upper will connect to the lower
-		if(icon_state == "ladderup")
-			return
+	var/const/climb_time = 2 SECONDS
 
+/obj/structure/ladder/initialize()
+	// the upper will connect to the lower
+	if(allowed_directions & DOWN) //we only want to do the top one, as it will initialize the ones before it.
 		for(var/obj/structure/ladder/L in GetBelow(src))
-			if(L.icon_state == "ladderup")
-				target = L
-				L.target = src
+			if(L.allowed_directions & UP)
+				target_down = L
+				L.target_up = src
 				return
+	update_icon()
 
-	Destroy()
-		if(target && icon_state == "ladderdown")
-			qdel(target)
-		return ..()
+/obj/structure/ladder/Destroy()
+	if(target_down)
+		target_down.target_up = null
+		target_down = null
+	if(target_up)
+		target_up.target_down = null
+		target_up = null
+	return ..()
 
-	attackby(obj/item/C as obj, mob/user as mob)
-		. = ..()
-		attack_hand(user)
+/obj/structure/ladder/attackby(obj/item/C as obj, mob/user as mob)
+	attack_hand(user)
+	return
+
+/obj/structure/ladder/attack_hand(var/mob/M)
+	if(!M.may_climb_ladders(src))
 		return
 
-	attack_hand(var/mob/M)
-		if(!target || !istype(target.loc, /turf))
-			M << "<span class='notice'>\The [src] is incomplete and can't be climbed.</span>"
+	var/obj/structure/ladder/target_ladder = getTargetLadder(M)
+	if(!target_ladder)
+		return
+	if(!M.Move(get_turf(src)))
+		to_chat(M, "<span class='notice'>You fail to reach \the [src].</span>")
+		return
+
+	var/direction = target_ladder == target_up ? "up" : "down"
+
+	M.visible_message("<span class='notice'>\The [M] begins climbing [direction] \the [src]!</span>",
+	"You begin climbing [direction] \the [src]!",
+	"You hear the grunting and clanging of a metal ladder being used.")
+
+	target_ladder.audible_message("<span class='notice'>You hear something coming [direction] \the [src]</span>")
+
+	if(do_after(M, climb_time, src))
+		climbLadder(M, target_ladder)
+
+/obj/structure/ladder/attack_ghost(var/mob/M)
+	var/target_ladder = getTargetLadder(M)
+	if(target_ladder)
+		M.forceMove(get_turf(target_ladder))
+
+/obj/structure/ladder/proc/getTargetLadder(var/mob/M)
+	if((!target_up && !target_down) || (target_up && !istype(target_up.loc, /turf) || (target_down && !istype(target_down.loc,/turf))))
+		to_chat(M, "<span class='notice'>\The [src] is incomplete and can't be climbed.</span>")
+		return
+	if(target_down && target_up)
+		var/direction = alert(M,"Do you want to go up or down?", "Ladder", "Up", "Down", "Cancel")
+
+		if(direction == "Cancel")
 			return
 
-		var/turf/T = target.loc
-		for(var/atom/A in T)
-			if(A.density)
-				M << "<span class='notice'>\A [A] is blocking \the [src].</span>"
-				return
+		if(!M.may_climb_ladders(src))
+			return
 
-		M.visible_message("<span class='notice'>\A [M] climbs [icon_state == "ladderup" ? "up" : "down"] \a [src]!</span>",
-			"You climb [icon_state == "ladderup"  ? "up" : "down"] \the [src]!",
-			"You hear the grunting and clanging of a metal ladder being used.")
-		M.Move(T)
+		switch(direction)
+			if("Up")
+				return target_up
+			if("Down")
+				return target_down
+	else
+		return target_down || target_up
 
-	CanPass(obj/mover, turf/source, height, airflow)
-		return airflow || !density
+/mob/proc/may_climb_ladders(var/ladder)
+	if(!Adjacent(ladder))
+		to_chat(src, "<span class='warning'>You need to be next to \the [ladder] to start climbing.</span>")
+		return FALSE
+	if(incapacitated())
+		to_chat(src, "<span class='warning'>You are physically unable to climb \the [ladder].</span>")
+		return FALSE
+	return TRUE
+
+/mob/observer/ghost/may_climb_ladders(var/ladder)
+	return TRUE
+
+/obj/structure/ladder/proc/climbLadder(var/mob/M, var/target_ladder)
+	var/turf/T = get_turf(target_ladder)
+	for(var/atom/A in T)
+		if(!A.CanPass(M, M.loc, 1.5, 0))
+			to_chat(M, "<span class='notice'>\The [A] is blocking \the [src].</span>")
+			return FALSE
+	return M.Move(T)
+
+/obj/structure/ladder/CanPass(obj/mover, turf/source, height, airflow)
+	return airflow || !density
+
+/obj/structure/ladder/update_icon()
+	icon_state = "ladder[!!(allowed_directions & UP)][!!(allowed_directions & DOWN)]"
+
+/obj/structure/ladder/up
+	allowed_directions = UP
+	icon_state = "ladder10"
+
+/obj/structure/ladder/updown
+	allowed_directions = UP|DOWN
+	icon_state = "ladder11"
 
 /obj/structure/stairs
 	name = "Stairs"
diff --git a/code/modules/multiz/turf.dm b/code/modules/multiz/turf.dm
index b358cd0fbbd..c34b395ed1b 100644
--- a/code/modules/multiz/turf.dm
+++ b/code/modules/multiz/turf.dm
@@ -1,88 +1,76 @@
+/turf/proc/CanZPass(atom/A, direction)
+	if(z == A.z) //moving FROM this turf
+		return direction == UP //can't go below
+	else
+		if(direction == UP) //on a turf below, trying to enter
+			return 0
+		if(direction == DOWN) //on a turf above, trying to enter
+			return !density
+
+/turf/simulated/open/CanZPass(atom, direction)
+	return 1
+
+/turf/space/CanZPass(atom, direction)
+	return 1
+
 /turf/simulated/open
 	name = "open space"
 	icon = 'icons/turf/space.dmi'
-	icon_state = "black"
-	alpha = 16
-	layer = 0
+	icon_state = ""
+	plane = PLANE_SPACE_BACKGROUND
 	density = 0
 	pathweight = 100000 //Seriously, don't try and path over this one numbnuts
 
 	var/turf/below
-	var/list/underlay_references
-	var/global/overlay_map = list()
+
+/turf/simulated/open/post_change()
+	..()
+	update()
 
 /turf/simulated/open/initialize()
 	..()
+	update()
+
+/turf/simulated/open/proc/update()
 	below = GetBelow(src)
-	ASSERT(HasBelow(z))
+	levelupdate()
+	for(var/atom/movable/A in src)
+		A.fall()
+	update_icon()
+
+/turf/simulated/open/update_dirt()
+	return 0
 
 /turf/simulated/open/Entered(var/atom/movable/mover)
-	// only fall down in defined areas (read: areas with artificial gravitiy)
-	if(!istype(below)) //make sure that there is actually something below
-		below = GetBelow(src)
-		if(!below)
-			return
-
-	// No gravity in space, apparently.
-	var/area/area = get_area(src)
-	if(area.name == "Space")
-		return
-
-	// Prevent pipes from falling into the void... if there is a pipe to support it.
-	if(mover.anchored || istype(mover, /obj/item/pipe) && \
-		(locate(/obj/structure/disposalpipe/up) in below) || \
-		 locate(/obj/machinery/atmospherics/pipe/zpipe/up in below))
-		return
-
-	// See if something prevents us from falling.
-	var/soft = 0
-	for(var/atom/A in below)
-		if(A.density)
-			if(!istype(A, /obj/structure/window))
-				return
-			else
-				var/obj/structure/window/W = A
-				if(W.is_fulltile())
-					return
-		// Dont break here, since we still need to be sure that it isnt blocked
-		if(istype(A, /obj/structure/stairs))
-			soft = 1
-
-	// We've made sure we can move, now.
-	mover.Move(below)
-
-	if(!soft)
-		if(!istype(mover, /mob))
-			if(istype(below, /turf/simulated/open))
-				mover.visible_message("\The [mover] falls from the deck above through \the [below]!", "You hear a whoosh of displaced air.")
-			else
-				mover.visible_message("\The [mover] falls from the deck above and slams into \the [below]!", "You hear something slam into the deck.")
-		else
-			var/mob/M = mover
-			if(istype(below, /turf/simulated/open))
-				below.visible_message("\The [mover] falls from the deck above through \the [below]!", "You hear a soft whoosh.[M.stat ? "" : ".. and some screaming."]")
-			else
-				M.visible_message("\The [mover] falls from the deck above and slams into \the [below]!", "You land on \the [below].", "You hear a soft whoosh and a crunch")
-
-			// Handle people getting hurt, it's funny!
-			if (istype(mover, /mob/living/carbon/human))
-				var/mob/living/carbon/human/H = mover
-				var/damage = 5
-				H.apply_damage(rand(0, damage), BRUTE, "head")
-				H.apply_damage(rand(0, damage), BRUTE, "chest")
-				H.apply_damage(rand(0, damage), BRUTE, "l_leg")
-				H.apply_damage(rand(0, damage), BRUTE, "r_leg")
-				H.apply_damage(rand(0, damage), BRUTE, "l_arm")
-				H.apply_damage(rand(0, damage), BRUTE, "r_arm")
-				H.weakened = max(H.weakened,2)
-				H.updatehealth()
+	..()
+	mover.fall()
 
 // override to make sure nothing is hidden
 /turf/simulated/open/levelupdate()
 	for(var/obj/O in src)
 		O.hide(0)
 
-// Straight copy from space.
+/turf/simulated/open/update_icon()
+	if(below)
+		underlays = list(image(icon = below.icon, icon_state = below.icon_state))
+
+	var/list/noverlays = list()
+	if(!istype(below,/turf/space))
+		noverlays += image(icon =icon, icon_state = "empty", layer = 2.45)
+
+	var/turf/simulated/T = get_step(src,NORTH)
+	if(istype(T) && !istype(T,/turf/simulated/open))
+		noverlays += image(icon ='icons/turf/cliff.dmi', icon_state = "metal", layer = 2.45)
+
+	var/obj/structure/stairs/S = locate() in below
+	if(S && S.loc == below)
+		var/image/I = image(icon = S.icon, icon_state = "below", dir = S.dir, layer = 2.45)
+		I.pixel_x = S.pixel_x
+		I.pixel_y = S.pixel_y
+		noverlays += I
+
+	overlays = noverlays
+
 /turf/simulated/open/attackby(obj/item/C as obj, mob/user as mob)
 	if (istype(C, /obj/item/stack/rods))
 		var/obj/structure/lattice/L = locate(/obj/structure/lattice, src)
@@ -90,12 +78,12 @@
 			return
 		var/obj/item/stack/rods/R = C
 		if (R.use(1))
-			user << "<span class='notice'>Constructing support lattice ...</span>"
+			to_chat(user, "<span class='notice'>You lay down the support lattice.</span>")
 			playsound(src, 'sound/weapons/Genhit.ogg', 50, 1)
-			ReplaceWithLattice()
+			new /obj/structure/lattice(locate(src.x, src.y, src.z))
 		return
 
-	if (istype(C, /obj/item/stack/tile/floor))
+	if (istype(C, /obj/item/stack/tile))
 		var/obj/structure/lattice/L = locate(/obj/structure/lattice, src)
 		if(L)
 			var/obj/item/stack/tile/floor/S = C
@@ -107,5 +95,15 @@
 			ChangeTurf(/turf/simulated/floor/airless)
 			return
 		else
-			user << "<span class='warning'>The plating is going to need some support.</span>"
-	return
\ No newline at end of file
+			to_chat(user, "<span class='warning'>The plating is going to need some support.</span>")
+
+	//To lay cable.
+	if(istype(C, /obj/item/stack/cable_coil))
+		var/obj/item/stack/cable_coil/coil = C
+		coil.turf_place(src, user)
+		return
+	return
+
+//Most things use is_plating to test if there is a cover tile on top (like regular floors)
+/turf/simulated/open/is_plating()
+	return 1
diff --git a/icons/turf/cliff.dmi b/icons/turf/cliff.dmi
new file mode 100644
index 00000000000..a54e13656ea
Binary files /dev/null and b/icons/turf/cliff.dmi differ