What types of rooms can I find in a Woodland Mansion in Minecraft?

This is a full, updated list of all the rooms (53 types of them!). The last version of this answer did not contain all the rooms, so the Minecraft wiki helped me out. I included links to screenshots:

• Flower pot room. A room that seems to be a tribute to a wide variety of flowers. 5 different flower pots sit on a cobblestone surface.

• Rails and ladders room. A room with a cobblestone ring around the walls, with rails on top of it, and ladders placed on the walls of the ring. A single pumpkin sits on the wall facing the door.

• Office. A room with two types of tables made out of cobblestone stairs, and chairs to go with them. There are some flower pots and carpets on the tables.

• Checkerboard room. A room with a checkerboard pattern on the floor, and all the walls are lined with oak fences. There is a hidden chest placed above the door, containing loot similar to that of a dungeon.

• White tulip sanctuary. A room with cobblestone and a single flower pot in the wall.

• X room. A secret room with four walls lined with cobblestone patterns. A chest sits in the corner.

• Spider spawner room. A secret room filled with cobwebs, and a spider spawner in the center.

• Obsidian room. A secret room with a heap of obsidian, and within that heap is a block of diamond.

• Birch pillar room. A room with a desk with a flower pot on top, as well as a prominent arch in the center, made of birch fences, slabs, and stairs.

• Birch arch room. A room with a desk with a flower pot on top, as well as a prominent arch in the center, made of birch fences, slabs, and stairs.

• Small dining room. A small dining room or meeting room, with a table and chairs to go with it. The table has light gray carpets on it, with some black carpets in the middle. The upper walls are decorated with vent or chimney-like structures.

• Single bed bedroom. A bedroom with a bed (made out of carpets), a fireplace (made out of cobblestone) and a small tree (made out of a fence and 1 block of leaves).

• Small library. A small library or study room, the only things of note being the several bookcases and flower pot in the corner.

• Allium room. A room with a small vine-decorated oak stand, on which sits an array of potted allium. A full cauldron and a chest containing more allium sit nearby. The roof is made out of oak fences.

• Gray banner room. An altar-like room with a construction in the middle, made of cobblestone and cobblestone stairs which delimit a tiny, short passage with a banner at the end. There's a hidden chest behind the construction. A vindicator always generates here.

• Wheat farm. A room with a wheat farm. The water in the farm is covered with lily pads. Some, or even all of the crops may be missing.

• Blacksmith room. A room with arches made of polished andesite. There's an anvil and, in a corner, two lava blocked encased by polished andesite to prevent burning. Because Polished Andesite is a variant of stone, it may be replaced by blocks such as ore, gravel, or stone variants. A vindicator always generates here.

• Sapling room. A room with 2 layers of rows of dark oak saplings. Ladders go to the ceiling. There is a loot chest with dark oak saplings in it.

• Wool room. A room containing a pile of assorted blue, light blue and cyan wool.

• Tree chopping room. A room containing a tree and a chest which always has an iron axe with Efficiency I. The entrance to this room is always sealed off by a wall of planks.

• Mushroom farm. A room with a mushroom farm, as well as a table, a chair and an empty chest.

• Stem farm. A room with a two-stage, pumpkin and melon farm. A vindicator always generates here.

• Small empty storage room. A storage room with a lot of single chests. All of the chests are empty. A vindicator always generates here.

• Redstone jail. A room with a door-opening redstone circuit. The room is locked by 2 iron doors. There is a lever and some redstone dust to open both. Inside is a zone with cobblestone arches, with some brown carpets and a cauldron. A vindicator always generates here.

• Small jail. A room with a cell with cobblestone walls and a cauldron and brown carpets on the inside, and a chair and a table outside. A vindicator always generates here.

• Wood archway room. A room with a bunch of arches made of dark oak wood. A chest exists at the room's end, containing loot. A vindicator always generates here.

• Winding stairway room. A room with spiral staircase: a 1-wide, dead end, sloping and curving hallway that leads to a single chest, containing loot similar to that of a dungeon.

• Illager head room. An otherwise empty room containing only an illager pixel art.

• Curved stairs room. Some stairs leading up, decorated with an illager pixel art. The stairs curve towards the left or right at the base.

• Medium dining room. A dining room, with a table with a flower pot on it and stairs all around it, and what appears to be a serving counter in the corner. A chandelier hangs from the ceiling.

• Double bed bedroom. A long bedroom with pink and purple beds towards the rear, and a table with a flower pot in the corner.

• Triple bed bedroom. A room with 3 blue beds. Three Vindicators always generate here.

• Medium library. A lounge-like room with many bookcases and a table in the center with four flower pots on it, the flowers arranged by height.

• Straight stairs room. A straight staircase leading up, above which is decorated with an illager pixel art.

• Master bedroom. A large master bedroom with a regal bed. Banners hang from an ornate wall decoration above the doorway.

• Bedroom with loft. An interesting two-tiered bedroom, containing a sort of closet made of birch wood and two dark oak doors. A ladder near the entrance leads above to a loft with a chest and carpets simulating a bed.

• Grave room. A complex altar-like room with an overhead shrine-like structure made out of cobblestone. Two Vindicators and an Evoker always generate here.

• Cat statue room, Chicken statue room. A room dedicated to a large wool black cat / chicken statue situated in the center.

• Clean chest room. A secret room with 1 chest containing assorted spoils, with 4 dark oak fences and 4 torches for each corner of the otherwise empty room.

• Fake end portal room. A secret room with a platform of orange wool in the middle and a ring of green wool above it, giving it the appearance of a stronghold portal. A set of cobblestone stairs and cobblestone monster egg blocks allow access to the top of the wool ring, which has a trapped chest surrounded by two TNT blocks and containing two ender pearls. If the trap is sprung, the TNT will also break cobble stone monster egg blocks and swarm the player with silverfish.

• Roof-chests room. A secret room that is empty, and the walls have an indent on 4 blocks on each side. This room has 2 chests above it in a small, attic-like space.

• Large jail. A room with four cells with cobblestone walls and a cauldron and brown carpets on the inside. A vindicator always generates here.

• Large empty storage room. A room with a lot of double chests. The chests are all empty. A vindicator always generates here.

• Illager statue room. A room with a giant iillager statue made out of wool, with a giant torch-like object in its left hand. A lapis lazuli block is hidden inside the head.

• Nature room. A room wherein one corner has a flowing water "fountain" surrounded by andesite, and the opposite corner has a dark oak tree. Because Polished Andesite is a variant of stone, it may be replaced by blocks such as ore, gravel, or stone variants.

• Large dining room. A large dining hall. Multiple tables dot this room, and a chandelier hangs from the center ceiling. Two vindicators and an evoker always generate here.

• Conference room. A large gathering hall with a table in a U-shape, its outer edge surrounded by stairs. Two chandeliers hang from the ceiling. Two vindicators and an evoker always generate here.

• Large library. A large library/study room with three rows of large bookshelves, and arranged seating area.

• Map room. A room with a colored carpet on the table, seeming to represent a map, as well as some bookcases along the wall. Two vindicators and an evoker always generate here.

• Arena room. A room with an arena/stage surrounded with dark oak fences in the center. A ladder leads up to an overhead loft. A chest with loot can be found on this loft.

• Main entrance. A room with a staircase in the center, and three doors, one on every side of the room excluding the side with the staircase. Every mansion has one of these, and it's always adjacent to the front door.

• Hallway. Self-explanatory, right?

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