Regular decorations for legacy nether(except v6)

minetest supports this now

mods/MAPGEN/mcl_biomes/init.lua

@@ -1499,6 +1499,20 @@ local function register_dimension_biomes()
 		_mcl_biome_type = "hot",
 		_mcl_palette_index = 17,
 	})
+
+	minetest.register_decoration({
+		deco_type = "simple",
+		place_on = {"mcl_nether:netherrack","mcl_nether:glowstone","mcl_blackstone:nether_gold","mcl_nether:quartz_ore","mcl_core:gravel","mcl_nether:soul_sand"},
+		sidelen = 16,
+		fill_ratio = 10,
+		biomes = { "Nether" },
+		y_min = -31000,
+		y_max = mcl_vars.mg_nether_max,
+		decoration = "mcl_nether:netherrack",
+		flags = "all_floors",
+		param2 = 0,
+	})
+
 	minetest.register_biome({
 		name = "SoulsandValley",
 		node_filler = "mcl_nether:netherrack",
@@ -4100,6 +4114,51 @@ end
 -- Decorations in non-Overworld dimensions
 local function register_dimension_decorations()
 	--[[ NETHER ]]
+	--NETHER WASTES (Nether)
+	minetest.register_decoration({
+		deco_type = "simple",
+		place_on = {"mcl_nether:netherrack","mcl_nether:magma"},
+		sidelen = 16,
+		fill_ratio = 0.04,
+		biomes = {"Nether"},
+		y_min = mcl_vars.mg_lava_nether_max + 1,
+		y_max = mcl_vars.mg_nether_max  - 1,
+		flags = "all_floors",
+		decoration = "mcl_fire:eternal_fire",
+	})
+	minetest.register_decoration({
+		deco_type = "simple",
+		place_on = {"mcl_nether:netherrack"},
+		sidelen = 16,
+		fill_ratio = 0.013,
+		biomes = {"Nether"},
+		y_min = mcl_vars.mg_lava_nether_max + 1,
+		y_max = mcl_vars.mg_nether_max  - 1,
+		flags = "all_floors",
+		decoration = "mcl_mushrooms:mushroom_brown",
+	})
+	minetest.register_decoration({
+		deco_type = "simple",
+		place_on = {"mcl_nether:netherrack"},
+		sidelen = 16,
+		fill_ratio = 0.012,
+		biomes = {"Nether"},
+		y_min = mcl_vars.mg_lava_nether_max + 1,
+		y_max = mcl_vars.mg_nether_max  - 1,
+		flags = "all_floors",
+		decoration = "mcl_mushrooms:mushroom_red",
+	})
+	minetest.register_decoration({
+		deco_type = "simple",
+		place_on = {"mcl_nether:soul_sand"},
+		sidelen = 16,
+		fill_ratio = 0.0032,
+		biomes = {"Nether","SoulsandValley"},
+		y_min = mcl_vars.mg_lava_nether_max + 1,
+		y_max = mcl_vars.mg_nether_max  - 1,
+		flags = "all_floors",
+		decoration = "mcl_nether:nether_wart",
+	})
 
 	-- WARPED FOREST
 	minetest.register_decoration({
@@ -4109,7 +4168,7 @@ local function register_dimension_decorations()
 		fill_ratio = 0.02,
 		biomes = {"WarpedForest"},
 		y_min = mcl_vars.mg_lava_nether_max + 1,
-		y_max = mcl_vars.mg_lava_nether_max  - 10,
+		y_max = mcl_vars.mg_nether_max  - 10,
 		flags = "all_floors",
 		decoration = "mcl_crimson:warped_fungus",
 	})

mods/MAPGEN/mcl_mapgen_core/init.lua

@@ -1754,8 +1754,9 @@ else
 	nether_wart_chance = 170
 end
 -- Generate Nether decorations manually: Eternal fire, mushrooms, nether wart
--- Minetest's API does not support decorations in caves yet. :-(
+-- (only v6)
 local function generate_nether_decorations(minp, maxp, seed)
+	if mg_name == "v6" then
 		local pr_nether = PseudoRandom(seed+667)
 
 		if minp.y > mcl_vars.mg_nether_max or maxp.y < mcl_vars.mg_nether_min then
@@ -1778,9 +1779,7 @@ local function generate_nether_decorations(minp, maxp, seed)
 
 				spawn_func(bpos)
 			end
-
 		end
-
 		-- Eternal fire on netherrack
 		special_deco(rack, function(bpos)
 			-- Eternal fire on netherrack
@@ -1817,7 +1816,7 @@ local function generate_nether_decorations(minp, maxp, seed)
 				minetest.set_node(bpos, {name = "mcl_nether:nether_wart"})
 			end
 		end)
-
+	end
 end
 
 minetest.register_on_generated(function(minp, maxp, blockseed)