diff --git a/mods/ENTITIES/mcl_mobs/api.lua b/mods/ENTITIES/mcl_mobs/api.lua
index d85633421..94d6340ea 100644
--- a/mods/ENTITIES/mcl_mobs/api.lua
+++ b/mods/ENTITIES/mcl_mobs/api.lua
@@ -3562,7 +3562,7 @@ local mob_step = function(self, dtime)
 	end
 
 	-- mob plays random sound at times
-	if random(1, 70) == 1 then
+	if random(1, 100) == 1 then
 		mob_sound(self, "random", true)
 	end
 
@@ -3925,35 +3925,7 @@ end
 end -- END mobs:register_mob function
 
 
-
-
-
-
-
-
-
-
-
-
-
---BEGIN SPAWNING ALGORITHM
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
 -- count how many mobs of one type are inside an area
---[[
 local count_mobs = function(pos, mobtype)
 
 	local num = 0
@@ -3997,7 +3969,7 @@ local count_mobs = function(pos, mobtype)
 
 	return num
 end
-]]--
+
 
 -- global functions
 
@@ -4007,49 +3979,9 @@ function mobs:spawn_abm_check(pos, node, name)
 end
 
 
---[[
-	Custom elements changed:
-name:
-the mobs name
+function mobs:spawn_specific(name, nodes, neighbors, min_light, max_light,
+	interval, chance, aoc, min_height, max_height, day_toggle, on_spawn)
 
-dimension: 
-"overworld"
-"nether"
-"end"
-
-types of spawning:
-"air"
-"water"
-"ground"
-"lava"
-
-what is aoc???
-
-WARNING: BIOME INTEGRATION NEEDED -> How to get biome through lua??
-]]--
-
---this is where all of the spawning information is kept
-local spawn_dictionary = {
-	["overworld"] = {},
-	["nether"] = {},
-	["end"] = {}
-}
-
-function mobs:spawn_specific(
-	name,
-	dimension,
-	type_of_spawning, 
-	min_light, 
-	max_light, 
-	interval, 
-	chance, 
-	aoc, 
-	min_height, 
-	max_height, 
-	day_toggle, 
-	on_spawn)
-
-	
 	-- Do mobs spawn at all?
 	if not mobs_spawn then
 		return
@@ -4070,6 +4002,7 @@ function mobs:spawn_specific(
 
 		minetest.log("action",
 			string.format("[mobs] Chance setting for %s changed to %s (total: %s)", name, chance, aoc))
+
 	end
 
 	local spawn_action
@@ -4234,24 +4167,6 @@ function mobs:spawn_specific(
 		spawn_action(pos, node, active_object_count, active_object_count_wider, name)
 	end
 
-
-	--load information into the spawn dictionary
-	local key = #spawn_dictionary[dimension] + 1
-
-	spawn_dictionary[dimension][key] = {}
-	spawn_dictionary[dimension][key]["name"]       = name
-	spawn_dictionary[dimension][key]["type"]       = type_of_spawning
-	spawn_dictionary[dimension][key]["min_light"]  = min_light
-	spawn_dictionary[dimension][key]["max_light"]  = max_light
-	spawn_dictionary[dimension][key]["interval"]   = interval
-	spawn_dictionary[dimension][key]["chance"]     = chance
-	spawn_dictionary[dimension][key]["aoc"]        = aoc
-	spawn_dictionary[dimension][key]["min_height"] = min_height
-	spawn_dictionary[dimension][key]["max_height"] = max_height
-	spawn_dictionary[dimension][key]["day_toggle"] = day_toggle
-	spawn_dictionary[dimension][key]["on_spawn"]   = spawn_abm_action
-	
-	--[[
 	minetest.register_abm({
 		label = name .. " spawning",
 		nodenames = nodes,
@@ -4261,24 +4176,18 @@ function mobs:spawn_specific(
 		catch_up = false,
 		action = spawn_abm_action,
 	})
-	]]--
 end
 
 
 -- compatibility with older mob registration
--- we're going to forget about this for now -j4i
---[[
 function mobs:register_spawn(name, nodes, max_light, min_light, chance, active_object_count, max_height, day_toggle)
 
 	mobs:spawn_specific(name, nodes, {"air"}, min_light, max_light, 30,
 		chance, active_object_count, -31000, max_height, day_toggle)
 end
-]]--
 
 
---I'm not sure what this does but disabling it doesn't cause a crash -j4i
 -- MarkBu's spawn function
---[[
 function mobs:spawn(def)
 
 	local name = def.name
@@ -4297,160 +4206,6 @@ function mobs:spawn(def)
 	mobs:spawn_specific(name, nodes, neighbors, min_light, max_light, interval,
 		chance, active_object_count, min_height, max_height, day_toggle, on_spawn)
 end
-]]--
-
-
-local axis
---inner and outer part of square donut radius
-local inner = 1
-local outer = 70
-local int = {-1,1}
-local position_calculation = function(pos)
-
-	pos = vector.floor(pos)
-
-	--this is used to determine the axis buffer from the player
-	axis = math.random(0,1)
-
-	--cast towards the direction
-	if axis == 0 then --x
-		pos.x = pos.x + math.random(inner,outer)*int[math.random(1,2)]
-		pos.z = pos.z + math.random(-outer,outer)
-	else --z
-		pos.z = pos.z + math.random(inner,outer)*int[math.random(1,2)]
-		pos.x = pos.x + math.random(-outer,outer)
-	end
-	return(pos)
-end
-
---[[
-local decypher_limits_dictionary = {
-	["overworld"] = {mcl_vars.mg_overworld_min,mcl_vars.mg_overworld_max},
-	["nether"]    = {mcl_vars.mg_nether_min,   mcl_vars.mg_nether_max},
-	["end"]       = {mcl_vars.mg_end_min,      mcl_vars.mg_end_max}
-}
-]]--
-
-local function decypher_limits(posy)
-	--local min_max_table = decypher_limits_dictionary[dimension]
-	--return min_max_table[1],min_max_table[2]
-	posy = math.floor(posy)
-	return posy - 32, posy + 32
-end
-
-
---todo mob limiting
---MAIN LOOP
-local timer = 0
-minetest.register_globalstep(function(dtime)
-	timer = timer + dtime
-	if timer >= 15 then
-		timer = 0
-		for _,player in ipairs(minetest.get_connected_players()) do
-			for i = 1,math.random(5) do
-				local player_pos = player:get_pos()
-				local _,dimension = mcl_worlds.y_to_layer(player_pos.y)
-				local min,max = decypher_limits(player_pos.y)
-
-				local goal_pos = position_calculation(player_pos)
-				
-
-				local mob_def = spawn_dictionary[dimension][math.random(1,#spawn_dictionary[dimension])]
-
-				if not mob_def then --to catch a crazy error if it ever happens
-					minetest.log("error", "WARNING!! mob spawning attempted to index a NIL mob!")
-					goto continue
-				end
-
-				if mob_def.type == "ground" then
-
-					local spawning_position_list = minetest.find_nodes_in_area_under_air(vector.new(goal_pos.x,min,goal_pos.z), vector.new(goal_pos.x,max,goal_pos.z), {"group:solid"})
-
-					if #spawning_position_list <= 0 then
-						goto continue
-					end
-					
-					local spawning_position = spawning_position_list[math.random(1,#spawning_position_list)]
-
-					spawning_position.y = spawning_position.y + 1
-
-					local gotten_light = minetest.get_node_light(spawning_position)
-
-					if gotten_light and gotten_light >= mob_def.min_light and gotten_light <= mob_def.max_light then
-						minetest.add_entity(spawning_position, mob_def.name)
-					end
-				elseif mob_def.type == "air" then
-					local spawning_position_list = minetest.find_nodes_in_area(vector.new(goal_pos.x,min,goal_pos.z), vector.new(goal_pos.x,max,goal_pos.z), {"air"})
-
-					if #spawning_position_list <= 0 then
-						goto continue
-					end
-					
-					local spawning_position = spawning_position_list[math.random(1,#spawning_position_list)]
-
-					local gotten_light = minetest.get_node_light(spawning_position)
-
-					if gotten_light and gotten_light >= mob_def.min_light and gotten_light <= mob_def.max_light then
-						minetest.add_entity(spawning_position, mob_def.name)
-					end
-				elseif mob_def.type == "water" then
-					local spawning_position_list = minetest.find_nodes_in_area(vector.new(goal_pos.x,min,goal_pos.z), vector.new(goal_pos.x,max,goal_pos.z), {"group:water"})
-
-					if #spawning_position_list <= 0 then
-						goto continue
-					end
-					
-					local spawning_position = spawning_position_list[math.random(1,#spawning_position_list)]
-
-					local gotten_light = minetest.get_node_light(spawning_position)
-
-					if gotten_light and gotten_light >= mob_def.min_light and gotten_light <= mob_def.max_light then
-						minetest.add_entity(spawning_position, mob_def.name)
-					end
-				--elseif mob_def.type == "lava" then
-					--implement later
-				end
-				--local spawn minetest.find_nodes_in_area_under_air(vector.new(pos.x,pos.y-find_node_height,pos.z), vector.new(pos.x,pos.y+find_node_height,pos.z), {"group:solid"})
-
-
-				::continue:: --this is a safety catch
-			end
-		end
-	end
-end)
-
-
-
-
-
-
-
-
-
-
-
-
-
---END SPAWNING ALGORITHM
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
 
 
 -- register arrow for shoot attack
diff --git a/mods/ENTITIES/mobs_mc/agent.lua b/mods/ENTITIES/mobs_mc/agent.lua
index cc9910ee6..8fa7314cf 100644
--- a/mods/ENTITIES/mobs_mc/agent.lua
+++ b/mods/ENTITIES/mobs_mc/agent.lua
@@ -1,5 +1,5 @@
 --###################
---################### AGENT - seemingly unused
+--################### AGENT
 --###################
 
 local S = minetest.get_translator("mobs_mc")
diff --git a/mods/ENTITIES/mobs_mc/bat.lua b/mods/ENTITIES/mobs_mc/bat.lua
index b6825bbbf..103579b67 100644
--- a/mods/ENTITIES/mobs_mc/bat.lua
+++ b/mods/ENTITIES/mobs_mc/bat.lua
@@ -64,7 +64,7 @@ else
 end
 
 -- Spawn on solid blocks at or below Sea level and the selected light level
-mobs:spawn_specific("mobs_mc:bat", "overworld", "air", 0, maxlight, 20, 5000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.water-1)
+mobs:spawn_specific("mobs_mc:bat", mobs_mc.spawn.solid, {"air"}, 0, maxlight, 20, 5000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.water-1)
 
 
 -- spawn eggs
diff --git a/mods/ENTITIES/mobs_mc/blaze.lua b/mods/ENTITIES/mobs_mc/blaze.lua
index d56acdf38..fbffa7920 100644
--- a/mods/ENTITIES/mobs_mc/blaze.lua
+++ b/mods/ENTITIES/mobs_mc/blaze.lua
@@ -1,6 +1,6 @@
 -- daufinsyd
 -- My work is under the LGPL terms
--- Model and mobs_blaze.png see https://github.com/22i/minecraft-voxel-blender-models -hi 22i ~jordan4ibanez
+-- Model and mobs_blaze.png see https://github.com/22i/minecraft-voxel-blender-models
 -- blaze.lua partial copy of mobs_mc/ghast.lua
 
 local S = minetest.get_translator("mobs_mc")
@@ -128,7 +128,7 @@ mobs:register_mob("mobs_mc:blaze", {
 	end,
 })
 
-mobs:spawn_specific("mobs_mc:blaze", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 5000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:blaze", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 5000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- Blaze fireball
 mobs:register_arrow("mobs_mc:blaze_fireball", {
diff --git a/mods/ENTITIES/mobs_mc/chicken.lua b/mods/ENTITIES/mobs_mc/chicken.lua
index 397b6b8da..325371e2b 100644
--- a/mods/ENTITIES/mobs_mc/chicken.lua
+++ b/mods/ENTITIES/mobs_mc/chicken.lua
@@ -100,7 +100,7 @@ mobs:register_mob("mobs_mc:chicken", {
 })
 
 --spawn
-mobs:spawn_specific("mobs_mc:chicken", "overworld", "ground", 9, minetest.LIGHT_MAX+1, 30, 17000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:chicken", mobs_mc.spawn.grassland, {"air"}, 9, minetest.LIGHT_MAX+1, 30, 17000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:chicken", S("Chicken"), "mobs_mc_spawn_icon_chicken.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/cow+mooshroom.lua b/mods/ENTITIES/mobs_mc/cow+mooshroom.lua
index a094d6d35..005af2980 100644
--- a/mods/ENTITIES/mobs_mc/cow+mooshroom.lua
+++ b/mods/ENTITIES/mobs_mc/cow+mooshroom.lua
@@ -145,9 +145,8 @@ mobs:register_mob("mobs_mc:mooshroom", mooshroom_def)
 
 
 -- Spawning
-mobs:spawn_specific("mobs_mc:cow", "overworld", "ground", 9, minetest.LIGHT_MAX+1, 30, 17000, 10, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
---WARNING: THIS NEEDS A BIOME INTEGRATION
-mobs:spawn_specific("mobs_mc:mooshroom", "overworld", "ground", 9, minetest.LIGHT_MAX+1, 30, 17000, 5, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:cow", mobs_mc.spawn.grassland, {"air"}, 9, minetest.LIGHT_MAX+1, 30, 17000, 10, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:mooshroom", mobs_mc.spawn.mushroom_island, {"air"}, 9, minetest.LIGHT_MAX+1, 30, 17000, 5, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn egg
 mobs:register_egg("mobs_mc:cow", S("Cow"), "mobs_mc_spawn_icon_cow.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/creeper.lua b/mods/ENTITIES/mobs_mc/creeper.lua
index f1f0a3ef6..de44ba8c6 100644
--- a/mods/ENTITIES/mobs_mc/creeper.lua
+++ b/mods/ENTITIES/mobs_mc/creeper.lua
@@ -39,8 +39,6 @@ mobs:register_mob("mobs_mc:creeper", {
 	runaway_from = { "mobs_mc:ocelot", "mobs_mc:cat" },
 	attack_type = "explode",
 
-	--hssssssssssss
-
 	explosion_strength = 3,
 	explosion_radius = 3.5,
 	explosion_damage_radius = 3.5,
@@ -140,9 +138,6 @@ mobs:register_mob("mobs_mc:creeper_charged", {
 	pathfinding = 1,
 	visual = "mesh",
 	mesh = "mobs_mc_creeper.b3d",
-
-	--BOOM
-	
 	textures = {
 		{"mobs_mc_creeper.png",
 		"mobs_mc_creeper_charge.png"},
@@ -253,7 +248,7 @@ mobs:register_mob("mobs_mc:creeper_charged", {
 	glow = 3,
 })
 
-mobs:spawn_specific("mobs_mc:creeper", "overworld", "ground", 0, 7, 20, 16500, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:creeper", mobs_mc.spawn.solid, {"air"}, 0, 7, 20, 16500, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:creeper", S("Creeper"), "mobs_mc_spawn_icon_creeper.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/enderman.lua b/mods/ENTITIES/mobs_mc/enderman.lua
index ca3bc84ce..f93f131cb 100644
--- a/mods/ENTITIES/mobs_mc/enderman.lua
+++ b/mods/ENTITIES/mobs_mc/enderman.lua
@@ -562,11 +562,11 @@ mobs:register_mob("mobs_mc:enderman", {
 
 
 -- End spawn
-mobs:spawn_specific("mobs_mc:enderman", "end", "ground", 0, minetest.LIGHT_MAX+1, 30, 3000, 12, mobs_mc.spawn_height.end_min, mobs_mc.spawn_height.end_max)
+mobs:spawn_specific("mobs_mc:enderman", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 3000, 12, mobs_mc.spawn_height.end_min, mobs_mc.spawn_height.end_max)
 -- Overworld spawn
-mobs:spawn_specific("mobs_mc:enderman", "overworld", "ground", 0, 7, 30, 19000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:enderman", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 19000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 -- Nether spawn (rare)
-mobs:spawn_specific("mobs_mc:enderman", "nether", "ground", 0, 7, 30, 27500, 4, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:enderman", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 27500, 4, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:enderman", S("Enderman"), "mobs_mc_spawn_icon_enderman.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/ghast.lua b/mods/ENTITIES/mobs_mc/ghast.lua
index e2f6b1369..7aed9395e 100644
--- a/mods/ENTITIES/mobs_mc/ghast.lua
+++ b/mods/ENTITIES/mobs_mc/ghast.lua
@@ -75,7 +75,7 @@ mobs:register_mob("mobs_mc:ghast", {
 })
 
 
-mobs:spawn_specific("mobs_mc:ghast", "nether", "air", 0, minetest.LIGHT_MAX+1, 30, 18000, 2, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:ghast", mobs_mc.spawn.nether, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 18000, 2, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- fireball (projectile)
 mobs:register_arrow("mobs_mc:fireball", {
diff --git a/mods/ENTITIES/mobs_mc/guardian_elder.lua b/mods/ENTITIES/mobs_mc/guardian_elder.lua
index 089f6e38f..a58a4a5b7 100644
--- a/mods/ENTITIES/mobs_mc/guardian_elder.lua
+++ b/mods/ENTITIES/mobs_mc/guardian_elder.lua
@@ -106,7 +106,7 @@ mobs:register_mob("mobs_mc:guardian_elder", {
 	view_range = 16,
 })
 
--- Spawning disabled due to size issues <- what do you mean? -j4i
+-- Spawning disabled due to size issues
 -- TODO: Re-enable spawning
 -- mobs:spawn_specific("mobs_mc:guardian_elder", mobs_mc.spawn.water, mobs_mc.spawn_water, 0, minetest.LIGHT_MAX+1, 30, 40000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.water-18)
 
diff --git a/mods/ENTITIES/mobs_mc/horse.lua b/mods/ENTITIES/mobs_mc/horse.lua
index 00c292c1d..3da63831e 100644
--- a/mods/ENTITIES/mobs_mc/horse.lua
+++ b/mods/ENTITIES/mobs_mc/horse.lua
@@ -510,8 +510,8 @@ mobs:register_mob("mobs_mc:mule", mule)
 
 --===========================
 --Spawn Function
-mobs:spawn_specific("mobs_mc:horse", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
-mobs:spawn_specific("mobs_mc:donkey", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:horse", mobs_mc.spawn.grassland_savanna, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:donkey", mobs_mc.spawn.grassland_savanna, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:horse", S("Horse"), "mobs_mc_spawn_icon_horse.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/llama.lua b/mods/ENTITIES/mobs_mc/llama.lua
index 0efb8e0ab..36d020a65 100644
--- a/mods/ENTITIES/mobs_mc/llama.lua
+++ b/mods/ENTITIES/mobs_mc/llama.lua
@@ -217,7 +217,7 @@ mobs:register_mob("mobs_mc:llama", {
 })
 
 --spawn
-mobs:spawn_specific("mobs_mc:llama", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 5, mobs_mc.spawn_height.water+15, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:llama", mobs_mc.spawn.savanna, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15000, 5, mobs_mc.spawn_height.water+15, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:llama", S("Llama"), "mobs_mc_spawn_icon_llama.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/ocelot.lua b/mods/ENTITIES/mobs_mc/ocelot.lua
index 3b5273185..eca74d3ba 100644
--- a/mods/ENTITIES/mobs_mc/ocelot.lua
+++ b/mods/ENTITIES/mobs_mc/ocelot.lua
@@ -152,9 +152,6 @@ mobs:register_mob("mobs_mc:cat", cat)
 local base_spawn_chance = 5000
 
 -- Spawn ocelot
---they get the same as the llama because I'm trying to rework so much of this code right now -j4i
-mobs:spawn_specific("mobs_mc:ocelot", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 5, mobs_mc.spawn_height.water+15, mobs_mc.spawn_height.overworld_max)
---[[
 mobs:spawn({
 	name = "mobs_mc:ocelot",
 	nodes = mobs_mc.spawn.jungle,
@@ -166,8 +163,8 @@ mobs:spawn({
 	min_height = mobs_mc.spawn_height.water+1, -- Right above ocean level
 	max_height = mobs_mc.spawn_height.overworld_max,
 	on_spawn = function(self, pos)
-		 Note: Minecraft has a 1/3 spawn failure rate.
-		In this mod it is emulated by reducing the spawn rate accordingly (see above). 
+		--[[ Note: Minecraft has a 1/3 spawn failure rate.
+		In this mod it is emulated by reducing the spawn rate accordingly (see above). ]]
 
 		-- 1/7 chance to spawn 2 ocelot kittens
 		if pr:next(1,7) == 1 then
@@ -210,7 +207,6 @@ mobs:spawn({
 		end
 	end,
 })
-]]--
 
 -- spawn eggs
 -- FIXME: The spawn icon shows a cat texture, not an ocelot texture
diff --git a/mods/ENTITIES/mobs_mc/parrot.lua b/mods/ENTITIES/mobs_mc/parrot.lua
index c67263fb9..407cb4466 100644
--- a/mods/ENTITIES/mobs_mc/parrot.lua
+++ b/mods/ENTITIES/mobs_mc/parrot.lua
@@ -90,8 +90,8 @@ mobs:register_mob("mobs_mc:parrot", {
 
 })
 
--- Parrots spawn rarely in jungles. TODO: Also check for jungle *biome* <- I'll get to this eventually -j4i
-mobs:spawn_specific("mobs_mc:parrot","overworld", "air", 0, minetest.LIGHT_MAX+1, 7, 30000, 1, mobs_mc.spawn_height.water+7, mobs_mc.spawn_height.overworld_max)
+-- Parrots spawn rarely in jungles. TODO: Also check for jungle *biome*
+mobs:spawn_specific("mobs_mc:parrot", {"mcl_core:jungletree", "mcl_core:jungleleaves"}, {"air"}, 0, minetest.LIGHT_MAX+1, 7, 30000, 1, mobs_mc.spawn_height.water+7, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:parrot", S("Parrot"), "mobs_mc_spawn_icon_parrot.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/pig.lua b/mods/ENTITIES/mobs_mc/pig.lua
index 143fcb495..38700b6ca 100644
--- a/mods/ENTITIES/mobs_mc/pig.lua
+++ b/mods/ENTITIES/mobs_mc/pig.lua
@@ -182,7 +182,7 @@ mobs:register_mob("mobs_mc:pig", {
 	end,
 })
 
-mobs:spawn_specific("mobs_mc:pig", "overworld", "ground", 9, minetest.LIGHT_MAX+1, 30, 15000, 8, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:pig", mobs_mc.spawn.grassland, {"air"}, 9, minetest.LIGHT_MAX+1, 30, 15000, 8, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:pig", S("Pig"), "mobs_mc_spawn_icon_pig.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/polar_bear.lua b/mods/ENTITIES/mobs_mc/polar_bear.lua
index 745c13a26..459ca29b4 100644
--- a/mods/ENTITIES/mobs_mc/polar_bear.lua
+++ b/mods/ENTITIES/mobs_mc/polar_bear.lua
@@ -67,7 +67,7 @@ mobs:register_mob("mobs_mc:polar_bear", {
 })
 
 
-mobs:spawn_specific("mobs_mc:polar_bear", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 7000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:polar_bear", mobs_mc.spawn.snow, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 7000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn egg
 mobs:register_egg("mobs_mc:polar_bear", S("Polar Bear"), "mobs_mc_spawn_icon_polarbear.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/rabbit.lua b/mods/ENTITIES/mobs_mc/rabbit.lua
index f09a70584..e167649f6 100644
--- a/mods/ENTITIES/mobs_mc/rabbit.lua
+++ b/mods/ENTITIES/mobs_mc/rabbit.lua
@@ -107,11 +107,8 @@ end
 mobs:register_mob("mobs_mc:killer_bunny", killer_bunny)
 
 -- Mob spawning rules.
--- Different skins depending on spawn location <- we'll get to this when the spawning algorithm is fleshed out
+-- Different skins depending on spawn location
 
-mobs:spawn_specific("mobs_mc:rabbit", "overworld", "ground", 9, minetest.LIGHT_MAX+1, 30, 15000, 8, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
-
---[[
 local spawn = {
 	name = "mobs_mc:rabbit",
 	neighbors = {"air"},
@@ -168,7 +165,6 @@ spawn_grass.on_spawn = function(self, pos)
 	self.object:set_properties({textures = self.base_texture})
 end
 mobs:spawn(spawn_grass)
-]]--
 
 -- Spawn egg
 mobs:register_egg("mobs_mc:rabbit", S("Rabbit"), "mobs_mc_spawn_icon_rabbit.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/sheep.lua b/mods/ENTITIES/mobs_mc/sheep.lua
index b3400ab5f..84650b4dd 100644
--- a/mods/ENTITIES/mobs_mc/sheep.lua
+++ b/mods/ENTITIES/mobs_mc/sheep.lua
@@ -303,7 +303,7 @@ mobs:register_mob("mobs_mc:sheep", {
 		end
 	end,
 })
-mobs:spawn_specific("mobs_mc:sheep", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:sheep", mobs_mc.spawn.grassland, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15000, 3, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:sheep", S("Sheep"), "mobs_mc_spawn_icon_sheep.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/shulker.lua b/mods/ENTITIES/mobs_mc/shulker.lua
index 583c5eed1..faaf2ac40 100644
--- a/mods/ENTITIES/mobs_mc/shulker.lua
+++ b/mods/ENTITIES/mobs_mc/shulker.lua
@@ -81,4 +81,4 @@ mobs:register_arrow("mobs_mc:shulkerbullet", {
 
 mobs:register_egg("mobs_mc:shulker", S("Shulker"), "mobs_mc_spawn_icon_shulker.png", 0)
 
-mobs:spawn_specific("mobs_mc:shulker", "end", "ground", 0, minetest.LIGHT_MAX+1, 30, 5000, 2, mobs_mc.spawn_height.end_min, mobs_mc.spawn_height.end_max)
+mobs:spawn_specific("mobs_mc:shulker", mobs_mc.spawn.end_city, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 5000, 2, mobs_mc.spawn_height.end_min, mobs_mc.spawn_height.end_max)
diff --git a/mods/ENTITIES/mobs_mc/skeleton+stray.lua b/mods/ENTITIES/mobs_mc/skeleton+stray.lua
index 84e51c517..cb12e905d 100644
--- a/mods/ENTITIES/mobs_mc/skeleton+stray.lua
+++ b/mods/ENTITIES/mobs_mc/skeleton+stray.lua
@@ -139,13 +139,13 @@ table.insert(stray.drops, {
 mobs:register_mob("mobs_mc:stray", stray)
 
 -- Overworld spawn
-mobs:spawn_specific("mobs_mc:skeleton", "overworld", "ground", 0, 7, 20, 17000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:skeleton", mobs_mc.spawn.solid, {"air"}, 0, 7, 20, 17000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 -- Nether spawn
-mobs:spawn_specific("mobs_mc:skeleton", "nether", "ground", 0, 7, 30, 10000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:skeleton", mobs_mc.spawn.nether_fortress, {"air"}, 0, 7, 30, 10000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- Stray spawn
 -- TODO: Spawn directly under the sky
-mobs:spawn_specific("mobs_mc:stray", "overworld", "ground", 0, 7, 20, 19000, 2, mobs_mc.spawn_height.water, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:stray", mobs_mc.spawn.snow, {"air"}, 0, 7, 20, 19000, 2, mobs_mc.spawn_height.water, mobs_mc.spawn_height.overworld_max)
 
 
 -- spawn eggs
diff --git a/mods/ENTITIES/mobs_mc/skeleton_wither.lua b/mods/ENTITIES/mobs_mc/skeleton_wither.lua
index d9de90d84..e4a1f86fc 100644
--- a/mods/ENTITIES/mobs_mc/skeleton_wither.lua
+++ b/mods/ENTITIES/mobs_mc/skeleton_wither.lua
@@ -94,7 +94,7 @@ mobs:register_mob("mobs_mc:witherskeleton", {
 })
 
 --spawn
-mobs:spawn_specific("mobs_mc:witherskeleton", "nether", "ground", 0, 7, 30, 5000, 5, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:witherskeleton", mobs_mc.spawn.nether_fortress, {"air"}, 0, 7, 30, 5000, 5, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:witherskeleton", S("Wither Skeleton"), "mobs_mc_spawn_icon_witherskeleton.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/slime+magma_cube.lua b/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
index 2f9e8c8a9..fd1f92bb4 100644
--- a/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
+++ b/mods/ENTITIES/mobs_mc/slime+magma_cube.lua
@@ -157,9 +157,9 @@ mobs:register_mob("mobs_mc:slime_tiny", slime_tiny)
 local smin = mobs_mc.spawn_height.overworld_min
 local smax = mobs_mc.spawn_height.water - 23
 
-mobs:spawn_specific("mobs_mc:slime_tiny", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 12000, 4, smin, smax)
-mobs:spawn_specific("mobs_mc:slime_small", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 8500, 4, smin, smax)
-mobs:spawn_specific("mobs_mc:slime_big", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 10000, 4, smin, smax)
+mobs:spawn_specific("mobs_mc:slime_tiny", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 12000, 4, smin, smax)
+mobs:spawn_specific("mobs_mc:slime_small", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 8500, 4, smin, smax)
+mobs:spawn_specific("mobs_mc:slime_big", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 10000, 4, smin, smax)
 
 -- Magma cube
 local magma_cube_big = {
@@ -272,13 +272,13 @@ mobs:register_mob("mobs_mc:magma_cube_tiny", magma_cube_tiny)
 local mmin = mobs_mc.spawn_height.nether_min
 local mmax = mobs_mc.spawn_height.nether_max
 
-mobs:spawn_specific("mobs_mc:magma_cube_tiny", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mmin, mmax)
-mobs:spawn_specific("mobs_mc:magma_cube_small", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 15500, 4, mmin, mmax)
-mobs:spawn_specific("mobs_mc:magma_cube_big", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 16000, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_tiny", mobs_mc.spawn.nether, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15000, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_small", mobs_mc.spawn.nether, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 15500, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_big", mobs_mc.spawn.nether, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 16000, 4, mmin, mmax)
 
---mobs:spawn_specific("mobs_mc:magma_cube_tiny", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11000, 4, mmin, mmax)
---mobs:spawn_specific("mobs_mc:magma_cube_small", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11100, 4, mmin, mmax)
---mobs:spawn_specific("mobs_mc:magma_cube_big", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11200, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_tiny", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11000, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_small", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11100, 4, mmin, mmax)
+mobs:spawn_specific("mobs_mc:magma_cube_big", mobs_mc.spawn.nether_fortress, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 11200, 4, mmin, mmax)
 
 
 -- spawn eggs
diff --git a/mods/ENTITIES/mobs_mc/spider.lua b/mods/ENTITIES/mobs_mc/spider.lua
index 1361e6a3a..0bb03a9c7 100644
--- a/mods/ENTITIES/mobs_mc/spider.lua
+++ b/mods/ENTITIES/mobs_mc/spider.lua
@@ -87,7 +87,7 @@ cave_spider.sounds.base_pitch = 1.25
 mobs:register_mob("mobs_mc:cave_spider", cave_spider)
 
 
-mobs:spawn_specific("mobs_mc:spider", "overworld", "ground", 0, 7, 30, 17000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:spider", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 17000, 2, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:spider", S("Spider"), "mobs_mc_spawn_icon_spider.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/squid.lua b/mods/ENTITIES/mobs_mc/squid.lua
index 2dbb7c557..1877a2104 100644
--- a/mods/ENTITIES/mobs_mc/squid.lua
+++ b/mods/ENTITIES/mobs_mc/squid.lua
@@ -62,7 +62,7 @@ mobs:register_mob("mobs_mc:squid", {
 
 local water = mobs_mc.spawn_height.water
 --name, nodes, neighbours, minlight, maxlight, interval, chance, active_object_count, min_height, max_height
-mobs:spawn_specific("mobs_mc:squid", "overworld", "water", 0, minetest.LIGHT_MAX+1, 30, 5500, 3, water-16, water)
+mobs:spawn_specific("mobs_mc:squid", mobs_mc.spawn.water, {mobs_mc.items.water_source}, 0, minetest.LIGHT_MAX+1, 30, 5500, 3, water-16, water)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:squid", S("Squid"), "mobs_mc_spawn_icon_squid.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/villager.lua b/mods/ENTITIES/mobs_mc/villager.lua
index 0b53d8015..68644266f 100644
--- a/mods/ENTITIES/mobs_mc/villager.lua
+++ b/mods/ENTITIES/mobs_mc/villager.lua
@@ -1074,7 +1074,7 @@ mobs:register_mob("mobs_mc:villager", {
 
 
 
-mobs:spawn_specific("mobs_mc:villager", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 20, 4, mobs_mc.spawn_height.water+1, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:villager", mobs_mc.spawn.village, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 20, 4, mobs_mc.spawn_height.water+1, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:villager", S("Villager"), "mobs_mc_spawn_icon_villager.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/villager_zombie.lua b/mods/ENTITIES/mobs_mc/villager_zombie.lua
index bcede2183..09539fa76 100644
--- a/mods/ENTITIES/mobs_mc/villager_zombie.lua
+++ b/mods/ENTITIES/mobs_mc/villager_zombie.lua
@@ -146,8 +146,8 @@ mobs:register_mob("mobs_mc:villager_zombie", {
 	harmed_by_heal = true,
 })
 
-mobs:spawn_specific("mobs_mc:villager_zombie", "overworld", "ground", 0, 7, 30, 4090, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
-mobs:spawn_specific("mobs_mc:villager_zombie", "overworld", "ground", 0, 7, 30, 60000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:villager_zombie", mobs_mc.spawn.village, {"air"}, 0, 7, 30, 4090, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:villager_zombie", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 60000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:villager_zombie", S("Zombie Villager"), "mobs_mc_spawn_icon_zombie_villager.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/witch.lua b/mods/ENTITIES/mobs_mc/witch.lua
index f9f9b8d1f..383cbd36f 100644
--- a/mods/ENTITIES/mobs_mc/witch.lua
+++ b/mods/ENTITIES/mobs_mc/witch.lua
@@ -99,7 +99,7 @@ mobs:register_arrow("mobs_mc:potion_arrow", {
 	end
 })
 
--- TODO: Spawn when witch works properly <- eventually -j4i
+-- TODO: Spawn when witch works properly
 --mobs:spawn_specific("mobs_mc:witch", mobs_mc.spawn.jungle, {"air"}, 0, minetest.LIGHT_MAX-6, 12, 20000, 2, mobs_mc.spawn_height.water-6, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
diff --git a/mods/ENTITIES/mobs_mc/wolf.lua b/mods/ENTITIES/mobs_mc/wolf.lua
index 953c2df72..fe3031895 100644
--- a/mods/ENTITIES/mobs_mc/wolf.lua
+++ b/mods/ENTITIES/mobs_mc/wolf.lua
@@ -232,6 +232,6 @@ end
 mobs:register_mob("mobs_mc:dog", dog)
 
 -- Spawn
-mobs:spawn_specific("mobs_mc:wolf", "overworld", "ground", 0, minetest.LIGHT_MAX+1, 30, 9000, 7, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:wolf", mobs_mc.spawn.wolf, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 9000, 7, mobs_mc.spawn_height.water+3, mobs_mc.spawn_height.overworld_max)
 
 mobs:register_egg("mobs_mc:wolf", S("Wolf"), "mobs_mc_spawn_icon_wolf.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/zombie.lua b/mods/ENTITIES/mobs_mc/zombie.lua
index 64f99d34d..df9727d34 100644
--- a/mods/ENTITIES/mobs_mc/zombie.lua
+++ b/mods/ENTITIES/mobs_mc/zombie.lua
@@ -135,11 +135,11 @@ mobs:register_mob("mobs_mc:baby_husk", baby_husk)
 
 -- Spawning
 
-mobs:spawn_specific("mobs_mc:zombie", "overworld", "ground", 0, 7, 30, 6000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:zombie", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 6000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 -- Baby zombie is 20 times less likely than regular zombies
-mobs:spawn_specific("mobs_mc:baby_zombie", "overworld", "ground", 0, 7, 30, 60000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
-mobs:spawn_specific("mobs_mc:husk", "overworld", "ground", 0, 7, 30, 6500, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
-mobs:spawn_specific("mobs_mc:baby_husk", "overworld", "ground", 0, 7, 30, 65000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:baby_zombie", mobs_mc.spawn.solid, {"air"}, 0, 7, 30, 60000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:husk", mobs_mc.spawn.desert, {"air"}, 0, 7, 30, 6500, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:baby_husk", mobs_mc.spawn.desert, {"air"}, 0, 7, 30, 65000, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- Spawn eggs
 mobs:register_egg("mobs_mc:husk", S("Husk"), "mobs_mc_spawn_icon_husk.png", 0)
diff --git a/mods/ENTITIES/mobs_mc/zombiepig.lua b/mods/ENTITIES/mobs_mc/zombiepig.lua
index e996425c8..8c29a4bff 100644
--- a/mods/ENTITIES/mobs_mc/zombiepig.lua
+++ b/mods/ENTITIES/mobs_mc/zombiepig.lua
@@ -111,12 +111,12 @@ baby_pigman.child = 1
 mobs:register_mob("mobs_mc:baby_pigman", baby_pigman)
 
 -- Regular spawning in the Nether
-mobs:spawn_specific("mobs_mc:pigman", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 6000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:pigman", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 6000, 3, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 -- Baby zombie is 20 times less likely than regular zombies
-mobs:spawn_specific("mobs_mc:baby_pigman", "nether", "ground", 0, minetest.LIGHT_MAX+1, 30, 100000, 4, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
+mobs:spawn_specific("mobs_mc:baby_pigman", mobs_mc.spawn.solid, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 100000, 4, mobs_mc.spawn_height.nether_min, mobs_mc.spawn_height.nether_max)
 
 -- Spawning in Nether portals in the Overworld
---mobs:spawn_specific("mobs_mc:pigman", mobs_mc.spawn.nether_portal, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 500, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
+mobs:spawn_specific("mobs_mc:pigman", mobs_mc.spawn.nether_portal, {"air"}, 0, minetest.LIGHT_MAX+1, 30, 500, 4, mobs_mc.spawn_height.overworld_min, mobs_mc.spawn_height.overworld_max)
 
 -- spawn eggs
 mobs:register_egg("mobs_mc:pigman", S("Zombie Pigman"), "mobs_mc_spawn_icon_zombie_pigman.png", 0)