diff --git a/mods/MAPGEN/mcl_mapgen_core/init.lua b/mods/MAPGEN/mcl_mapgen_core/init.lua
index f9745b471..5a6082533 100644
--- a/mods/MAPGEN/mcl_mapgen_core/init.lua
+++ b/mods/MAPGEN/mcl_mapgen_core/init.lua
@@ -2168,18 +2168,18 @@ mcl_mapgen_core.register_generator("main", basic, basic_node, 1, true)
 
 mcl_mapgen_core.register_generator("structures",nil, function(minp, maxp, blockseed)
 	local gennotify = minetest.get_mapgen_object("gennotify")
-	local pr = PseudoRandom(blockseed + 42)
 	local has_struct = {}
 	local poshash = minetest.hash_node_position(minp)
 	for _,struct in pairs(mcl_structures.registered_structures) do
 		if struct.deco_id then
+			local pr = PseudoRandom(blockseed + 42)
 			local has = false
 			if has_struct[struct.name] == nil then has_struct[struct.name] = {}	end
 			for _, pos in pairs(gennotify["decoration#"..struct.deco_id] or {}) do
 				local realpos = vector.offset(pos,0,1,0)
 				minetest.remove_node(realpos)
 				if struct.chunk_probability == nil or (not has and pr:next(1,struct.chunk_probability) == 1 ) then
-					mcl_structures.place_structure(realpos,struct,pr)
+					mcl_structures.place_structure(realpos,struct,pr,blockseed)
 					has=true
 				end
 			end
diff --git a/mods/MAPGEN/mcl_structures/api.lua b/mods/MAPGEN/mcl_structures/api.lua
index 4e017b502..a4a3e59cf 100644
--- a/mods/MAPGEN/mcl_structures/api.lua
+++ b/mods/MAPGEN/mcl_structures/api.lua
@@ -38,7 +38,7 @@ function mcl_structures.find_highest_y(pp)
 	return y
 end
 
-function mcl_structures.place_structure(pos, def, pr)
+function mcl_structures.place_structure(pos, def, pr, blockseed)
 	if not def then	return end
 	local logging = not def.terrain_feature
 	local y_offset = 0
@@ -83,7 +83,7 @@ function mcl_structures.place_structure(pos, def, pr)
 			end
 		end
 	end
-	if def.on_place and not def.on_place(pos,def,pr) then
+	if def.on_place and not def.on_place(pos,def,pr,blockseed) then
 		if logging then
 			minetest.log("warning","[mcl_structures] "..def.name.." at "..minetest.pos_to_string(pp).." not placed. Conditions not satisfied.")
 		end
@@ -94,20 +94,20 @@ function mcl_structures.place_structure(pos, def, pr)
 		local r = pr:next(1,#def.filenames)
 		local file = def.filenames[r]
 		if file then
-			local ap = function(pos,def,pr) end
+			local ap = function(pos,def,pr,blockseed) end
 			if def.after_place then ap = def.after_place  end
 
 			mcl_structures.place_schematic(pp, file, "random", nil, true, "place_center_x,place_center_z",function(p)
-				if def.loot then generate_loot(pos,def,pr) end
-				return ap(pos,def,pr)
+				if def.loot then generate_loot(pos,def,pr,blockseed) end
+				return ap(pos,def,pr,blockseed)
 			end,pr)
 			if logging then
 				minetest.log("action","[mcl_structures] "..def.name.." placed at "..minetest.pos_to_string(pp))
 			end
 			return true
 		end
-	elseif def.place_func and def.place_func(pos,def,pr) then
-		if not def.after_place or ( def.after_place  and def.after_place(pos,def,pr) ) then
+	elseif def.place_func and def.place_func(pos,def,pr,blockseed) then
+		if not def.after_place or ( def.after_place  and def.after_place(pos,def,pr,blockseed) ) then
 			if logging then
 				minetest.log("action","[mcl_structures] "..def.name.." placed at "..minetest.pos_to_string(pp))
 			end
diff --git a/mods/MAPGEN/mcl_structures/init.lua b/mods/MAPGEN/mcl_structures/init.lua
index a77b3dbe4..0eafab584 100644
--- a/mods/MAPGEN/mcl_structures/init.lua
+++ b/mods/MAPGEN/mcl_structures/init.lua
@@ -336,7 +336,7 @@ minetest.register_chatcommand("spawnstruct", {
 		else
 			for n,d in pairs(mcl_structures.registered_structures) do
 				if n == param then
-					mcl_structures.place_structure(pos,d,pr)
+					mcl_structures.place_structure(pos,d,pr,math.random())
 					return true,message
 				end
 			end
diff --git a/mods/MAPGEN/tsm_railcorridors/init.lua b/mods/MAPGEN/tsm_railcorridors/init.lua
index 8bb0d7253..3f1e5b5a6 100644
--- a/mods/MAPGEN/tsm_railcorridors/init.lua
+++ b/mods/MAPGEN/tsm_railcorridors/init.lua
@@ -1097,11 +1097,40 @@ local function create_corridor_system(main_cave_coords)
 
 	-- At this point, all corridors were generated and all nodes were set.
 	-- We spawn the carts now
-	spawn_carts()
+	--spawn_carts()
 
 	return true
 end
 
+mcl_structures.register_structure("mineshaft",{
+	place_on = {"group:sand","group:grass_block","mcl_core:water_source","group:dirt","mcl_core:dirt_with_grass","mcl_core:gravel","group:material_stone"},
+	fill_ratio = 0.0001,
+	flags = "place_center_x, place_center_z, liquid_surface, force_placement, all_floors",
+	sidelen = 32,
+	--chunk_probability = 300,
+	y_max = 40,
+	y_min = mcl_vars.mg_overworld_min,
+	place_func = function(pos,def,pr,blockseed)
+		local r = pr:next(-50,-10)
+		local p = vector.offset(pos,0,r,0)
+		if p.y < mcl_vars.mg_overworld_min + 5 then
+			p.y = mcl_vars.mg_overworld_min + 5
+		end
+		if p.y > -10 then return end
+		local p1 = vector.offset(p,-def.sidelen,-def.sidelen,-def.sidelen)
+		local p2 = vector.offset(p,def.sidelen,def.sidelen,def.sidelen)
+		minetest.emerge_area(p1, p2, function(blockpos, action, calls_remaining, param)
+			if calls_remaining ~= 0 then return end
+			--minetest.log("lol")
+			InitRandomizer(blockseed)
+			create_corridor_system(p, pr)
+		end)
+		return true
+	end,
+
+})
+
+--[[ Old Generation code this is VERY slow
 -- The rail corridor algorithm starts here
 mcl_mapgen_core.register_generator("railcorridors", nil, function(minp, maxp, blockseed, _pr)
 	-- We re-init the randomizer for every mapchunk as we start generating in the middle of each mapchunk.
@@ -1112,9 +1141,7 @@ mcl_mapgen_core.register_generator("railcorridors", nil, function(minp, maxp, bl
 		local buffer = 5
 
 		-- Do up to 10 tries to start a corridor system
-		-- 5 Still seems to generate a lot of them and
-		-- makes this noticeably faster.
-		for t=1,5 do
+		for t=1,10 do
 			-- Get semi-random height in mapchunk
 			local y = pr:next(minp.y + buffer, maxp.y - buffer)
 			y = math.floor(math.max(height_min + buffer, math.min(height_max - buffer, y)))
@@ -1132,3 +1159,4 @@ mcl_mapgen_core.register_generator("railcorridors", nil, function(minp, maxp, bl
 		end
 	end
 end, 10)
+--]]
diff --git a/mods/MAPGEN/tsm_railcorridors/mod.conf b/mods/MAPGEN/tsm_railcorridors/mod.conf
index c846cff19..d1a9ada4a 100644
--- a/mods/MAPGEN/tsm_railcorridors/mod.conf
+++ b/mods/MAPGEN/tsm_railcorridors/mod.conf
@@ -1,4 +1,4 @@
 name = tsm_railcorridors
 author = UgnilJoZ
 description = Adds simple underground mines with railways and occasional treasure chests.
-depends = mcl_init, mcl_worlds, mcl_core, mcl_mapgen_core, mcl_loot, mcl_tnt, mcl_farming, mcl_mobspawners, mcl_minecarts
+depends = mcl_init, mcl_worlds, mcl_core, mcl_mapgen_core, mcl_loot, mcl_tnt, mcl_farming, mcl_mobspawners, mcl_minecarts, mcl_structures