diff --git a/mods/ctf/ctf_map/schem_map.lua b/mods/ctf/ctf_map/schem_map.lua
index 364b769..8d4cff8 100644
--- a/mods/ctf/ctf_map/schem_map.lua
+++ b/mods/ctf/ctf_map/schem_map.lua
@@ -5,25 +5,25 @@ minetest.register_alias("ctf_map:flag", "air")
 minetest.register_alias("ctf_map:ind_cobble", "ctf_map:cobble")
 minetest.register_alias("ctf_map:ind_stone", "ctf_map:stone")
 
-minetest.register_alias("flowers:mushroom_red", "air")
-minetest.register_alias("flowers:mushroom_brown", "air")
-minetest.register_alias("flowers:waterlily", "air")
-minetest.register_alias("flowers:rose", "air")
-minetest.register_alias("flowers:tulip", "air")
-minetest.register_alias("flowers:dandelion_yellow", "air")
-minetest.register_alias("flowers:geranium", "air")
-minetest.register_alias("flowers:viola", "air")
-minetest.register_alias("flowers:dandelion_white", "air")
-minetest.register_alias("flowers:chrysanthemum_green", "air")
-minetest.register_alias("default:grass_1", "air")
-minetest.register_alias("default:grass_2", "air")
-minetest.register_alias("default:grass_3", "air")
-minetest.register_alias("default:grass_4", "air")
-minetest.register_alias("default:sand_with_kelp", "default:sand")
-minetest.register_alias("default:grass_5", "air")
-minetest.register_alias("default:bush_leaves", "air")
-minetest.register_alias("default:bush_stem", "air")
-minetest.register_alias("default:stone_with_gold", "default:stone")
+minetest.register_alias_force("flowers:mushroom_red", "air")
+minetest.register_alias_force("flowers:mushroom_brown", "air")
+minetest.register_alias_force("flowers:waterlily", "air")
+minetest.register_alias_force("flowers:rose", "air")
+minetest.register_alias_force("flowers:tulip", "air")
+minetest.register_alias_force("flowers:dandelion_yellow", "air")
+minetest.register_alias_force("flowers:geranium", "air")
+minetest.register_alias_force("flowers:viola", "air")
+minetest.register_alias_force("flowers:dandelion_white", "air")
+minetest.register_alias_force("flowers:chrysanthemum_green", "air")
+minetest.register_alias_force("default:grass_1", "air")
+minetest.register_alias_force("default:grass_2", "air")
+minetest.register_alias_force("default:grass_3", "air")
+minetest.register_alias_force("default:grass_4", "air")
+minetest.register_alias_force("default:sand_with_kelp", "default:sand")
+minetest.register_alias_force("default:grass_5", "air")
+minetest.register_alias_force("default:bush_leaves", "air")
+minetest.register_alias_force("default:bush_stem", "air")
+minetest.register_alias_force("default:stone_with_gold", "default:stone")
 
 
 local max_r  = 120