[Suggestion] Add some biomes for caves levels

[TheBigEye]

• Add the Mushroom biome for the caves level
  • Red and Bown mushrooms has flowers
  • Big Red and Brown mushroom trees
  • Mycelium tiles patches
• Vine and Mossy biome for caverns level
  • Mossy rock instead of normal rock
  • Some ferns tiles
• Volcanic biome or Basalt deltas for the hell caves level
  • Magma tiles
  • Ash tiles