The Lost Room

The Lost Room

Requires Immersive Portals

What this mod adds

The Lost Room introduces a single, carefully crafted mystery into your Minecraft world: Room 10, a motel room that exists outside of normal space. A unique key — the Room 10 Key — can open a portal to it through any door in the Overworld.

The Key

There is exactly one Room 10 Key per world. It can be found in:

• Stronghold library or Woodland Mansion chests (1% chance by default, configurable)
• A Wandering Trader (20% chance per trader, costs 50 Emeralds + 20 Eyes of Ender — only offered if the key doesn't already exist elsewhere in the world)

The Portal

Right-click any door with the Key to open a portal to Room 10 in front of it. The Overworld door never physically opens — it becomes a window. 

• Only one portal can be active at a time. Using the Key on a second door while another portal is open does nothing.
• Shift+right-click to physically place the Key on the door (visible as a HUD icon when nearby).
• The portal stays open as long as the mirror door inside Room 10 is open, or the Key is on the Overworld door.

Inside Room 10

Room 10 is a fixed, hand-crafted motel room loaded in its own dimension. All Object powers are disabled inside.

Objects never disappear from the room. When the room resets, every Object found anywhere inside — in inventories, on the floor, in containers — is recovered and repositioned at its canonical spawn location. Nothing is permanently lost.

The reset: If the portal closes while the Key is still inside the room, every player in the room is killed (inventories lost) and the room resets to its initial state — completely reconstructed.

The exit — and the real power of Room 10: If you're inside with the Key and the portal has closed, you are not truly trapped. Interacting with the mirror door opens a destination selector: choose a specific door you've previously interacted with, a random Overworld door, or enter approximate coordinates. This makes Room 10 a fast-travel hub to virtually anywhere in the world 

Objects

Scattered across the world — in loot chests, on the ground, or in Room 10 itself — are 36 unique Objects. Each is a recognizable item given a hidden power.

Rules that apply to every Object:

• Only one copy per world. The mod enforces this continuously.
• Indestructible outside Room 10 (fire, explosions, lava, void — nothing destroys them as items).
• Powers only work outside of Room 10.
• The power of each Object is hidden until it activates for the first time. The tooltip is blank until then.

Objects are either items (held or in inventory) or block-objects (placeable blocks that gain a passive effect when placed in the world or held in inventory depending on them).

Two Objects are always present in Room 10 at world creation. The remaining 34 can spawn in any natural loot chest worldwide (1% chance per chest, configurable), weighted by rarity.

Object list (spoilers)

Items — passive (in inventory) or active (on use)

Block-Objects — place them in the world to activate

Planned features

• Object combinations: specific pairs of Objects carried together will alter or amplify their individual powers
• Lectern + Book & Quill fix: stabilise materialisation edge cases for complex written entries

Configuration

All major values are exposed in the Forge config (thelostroom-server.toml): key and Object spawn rates, Wandering Trader probabilities, door search radius, Pen power multiplier, and more.

Inspired by the TV series The Lost Room (2006).