public static bool changed = false;
        public static Texture2D[] oldTextures;
        public override void PostDraw(SpriteBatch spriteBatch, Color lightColor)
        {
            if (Main.time % 30 == 0)
            {
                if (Main.keyState.IsKeyDown(Microsoft.Xna.Framework.Input.Keys.O))
                {
                    if (!changed)
                    {
                        var fieldInfo = typeof(Main).GetField("underworldTexture", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
                        oldTextures = (Texture2D[])fieldInfo.GetValue(null);
                        Texture2D[] textures = new Texture2D[5];
                        textures[0] = mod.GetTexture("Background_50");
                        textures[1] = mod.GetTexture("Background_9");
                        textures[2] = mod.GetTexture("Background_113");
                        textures[3] = mod.GetTexture("Background_7");
                        textures[4] = mod.GetTexture("Background_0");
                        fieldInfo.SetValue(null, textures);
                        changed = true;
                        Main.NewText("changed to new");
                    }
                    else
                    {
                        var fieldInfo = typeof(Main).GetField("underworldTexture", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static);
                        fieldInfo.SetValue(null, oldTextures);
                        changed = false;
                        Main.NewText("changed back old");
                    }
                }
            }
            if (oldTextures != null) spriteBatch.Draw(oldTextures[0], new Rectangle(0, 0, 100, 500), lightColor);
        }