--- ../src-base/minecraft/net/minecraft/world/WorldType.java
+++ ../src-work/minecraft/net/minecraft/world/WorldType.java
@@ -114,4 +114,53 @@
         this.field_151361_l = true;
         return this;
     }
+
+    public net.minecraft.world.biome.WorldChunkManager getChunkManager(World world)
+    {
+        if (this == field_77138_c)
+        {
+            net.minecraft.world.gen.FlatGeneratorInfo flatgeneratorinfo = net.minecraft.world.gen.FlatGeneratorInfo.func_82651_a(world.func_72912_H().func_82571_y());
+            return new net.minecraft.world.biome.WorldChunkManagerHell(net.minecraft.world.biome.BiomeGenBase.func_180276_a(flatgeneratorinfo.func_82648_a(), net.minecraft.world.biome.BiomeGenBase.field_180279_ad), 0.5F);
+        }
+        else if (this == field_180272_g)
+        {
+            return new net.minecraft.world.biome.WorldChunkManagerHell(net.minecraft.world.biome.BiomeGenBase.field_76772_c, 0.0F);
+        }
+        else
+        {
+            return new net.minecraft.world.biome.WorldChunkManager(world);
+        }
+    }
+
+    public net.minecraft.world.chunk.IChunkProvider getChunkGenerator(World world, String generatorOptions)
+    {
+        if (this == field_77138_c) return new net.minecraft.world.gen.ChunkProviderFlat(world, world.func_72905_C(), world.func_72912_H().func_76089_r(), generatorOptions);
+        if (this == field_180272_g) return new net.minecraft.world.gen.ChunkProviderDebug(world);
+        return new net.minecraft.world.gen.ChunkProviderGenerate(world, world.func_72905_C(), world.func_72912_H().func_76089_r(), generatorOptions);
+    }
+
+    public int getMinimumSpawnHeight(World world)
+    {
+        return this == field_77138_c ? 4 : 64;
+    }
+
+    public double getHorizon(World world)
+    {
+        return this == field_77138_c ? 0.0D : 63.0D;
+    }
+
+    public double voidFadeMagnitude()
+    {
+        return this == field_77138_c ? 1.0D : 0.03125D;
+    }
+
+    public boolean handleSlimeSpawnReduction(java.util.Random random, World world)
+    {
+        return this == field_77138_c ? random.nextInt(4) != 1 : false;
+    }
+
+    /**
+     * Called when 'Create New World' button is pressed before starting game
+     */
+    public void onGUICreateWorldPress() { }
 }
