Collapsed house

Minecrafts caves and cliffs update adds more to caves but what about structures in caves? The collapsed house is found in these gravely patches covered in gravel. You have to dig your way in and this is where everything starts. These are big structures and have many undead mobs. New mobs also inhabit here. The new mob is the ghost. They look like a white zombie and have that swimming animation. They fly around like this slowly and have red eyes. Now more about the structure. The entrance leads to a door leading to the treasure room. There is a lava trap here. These can have iron swords and pickaxes and also fishing rods and its very rare to get one diamond. On the left and right there are lots of halls and many turns (making it like a maze) and will lead you to the room with beds and lots of cobwebs. Candles are here glowing dimly and there are barrels with books and enchantment books. Write ideas in comments.