diff --git a/maps/mountain_fortress_v3/functions.lua b/maps/mountain_fortress_v3/functions.lua
index 8119d0bc..62c7f78b 100644
--- a/maps/mountain_fortress_v3/functions.lua
+++ b/maps/mountain_fortress_v3/functions.lua
@@ -1224,7 +1224,13 @@ function Public.on_player_joined_game(event)
         local p = {x = player.position.x, y = player.position.y}
         local get_tile = surface.get_tile(p)
         if get_tile.valid and get_tile.name == 'out-of-map' then
-            player.teleport(surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5), surface)
+            local pos = surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5)
+            if pos then
+                player.teleport(pos, surface)
+            else
+                pos = game.forces.player.get_spawn_position(surface)
+                player.teleport(pos, surface)
+            end
         end
     end
 
diff --git a/maps/mountain_fortress_v3/ic/functions.lua b/maps/mountain_fortress_v3/ic/functions.lua
index 5e97e5fb..9ab3c175 100644
--- a/maps/mountain_fortress_v3/ic/functions.lua
+++ b/maps/mountain_fortress_v3/ic/functions.lua
@@ -332,7 +332,13 @@ local function check_if_players_are_in_nauvis(ic)
     for _, player in pairs(game.connected_players) do
         local main_surface = game.surfaces[ic.allowed_surface]
         if player.surface.name == 'nauvis' then
-            player.teleport(main_surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(main_surface), 3, 0, 5), main_surface)
+            local pos = main_surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(main_surface), 3, 0, 5)
+            if pos then
+                player.teleport(pos, main_surface)
+            else
+                pos = game.forces.player.get_spawn_position(main_surface)
+                player.teleport(pos, main_surface)
+            end
         end
     end
 end
diff --git a/maps/mountain_fortress_v3/icw/functions.lua b/maps/mountain_fortress_v3/icw/functions.lua
index 3808397f..45f79198 100644
--- a/maps/mountain_fortress_v3/icw/functions.lua
+++ b/maps/mountain_fortress_v3/icw/functions.lua
@@ -849,6 +849,10 @@ function Public.use_cargo_wagon_door_with_entity(icw, player, door)
         return
     end
 
+    if not wagon.entity or not wagon.entity.valid then
+        return
+    end
+
     player_data.fallback_surface = wagon.entity.surface.index
     player_data.fallback_position = {wagon.entity.position.x, wagon.entity.position.y}
 
diff --git a/maps/mountain_fortress_v3/locomotive.lua b/maps/mountain_fortress_v3/locomotive.lua
index 8a717deb..e93ec37d 100644
--- a/maps/mountain_fortress_v3/locomotive.lua
+++ b/maps/mountain_fortress_v3/locomotive.lua
@@ -1128,7 +1128,7 @@ local function gui_click(event)
             }
         )
 
-        this.locomotive_max_health = this.locomotive_max_health + 10000
+        this.locomotive_max_health = this.locomotive_max_health + 20000
 
         --[[
         this.locomotive_max_health = this.locomotive_max_health + (this.locomotive_max_health * 0.5)
@@ -1836,7 +1836,13 @@ local function on_player_changed_surface(event)
         if not surface or not surface.valid then
             return
         end
-        player.teleport(surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5), surface)
+        local pos = surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5)
+        if pos then
+            player.teleport(pos, surface)
+        else
+            pos = game.forces.player.get_spawn_position(surface)
+            player.teleport(pos, surface)
+        end
     end
 
     if string.sub(player.surface.name, 0, #map_name) ~= map_name then
diff --git a/modules/rpg/main.lua b/modules/rpg/main.lua
index ae8fd478..b19e73aa 100644
--- a/modules/rpg/main.lua
+++ b/modules/rpg/main.lua
@@ -1117,7 +1117,13 @@ local function on_player_used_capsule(event)
             end
         end
     elseif obj_name == 'warp-gate' then
-        player.teleport(surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5), surface)
+        local pos = surface.find_non_colliding_position('character', game.forces.player.get_spawn_position(surface), 3, 0, 5)
+        if pos then
+            player.teleport(pos, surface)
+        else
+            pos = game.forces.player.get_spawn_position(surface)
+            player.teleport(pos, surface)
+        end
         rpg_t.mana = 0
         Public.damage_player_over_time(player, math.random(8, 16))
         player.play_sound {path = 'utility/armor_insert', volume_modifier = 1}
diff --git a/modules/wave_defense/main.lua b/modules/wave_defense/main.lua
index a117b4d8..c49d3506 100644
--- a/modules/wave_defense/main.lua
+++ b/modules/wave_defense/main.lua
@@ -790,6 +790,12 @@ local function command_to_main_target(group, bypass)
 
     debug_print('get_main_command - got commands')
 
+    local surface_index = WD.get('surface_index')
+
+    if group.surface.index ~= surface_index then
+        return
+    end
+
     group.set_command(
         {
             type = defines.command.compound,