Lostworld.jar
by Worldman
Lostworld adds horror scenes that players reach by moving through unsettling dimensions, with a psychological meta-horror design on Forge for 1.20.1.
What it does
Players walk into creepy dimensions filled with scary entities, glitched liminal levels such as Level 2 and Level 6, endless mazes and strange libraries in which a Worldbrick appears. The mod is built around the idea that the game itself reacts to the player, so the experience is meant to feel as if something inside the computer has taken notice of the player.
The mod goes beyond the game window. Text files can be created and dropped onto the real-life Desktop with clues and binary codes, and custom Windows error pop-ups and dialog windows can be produced outside the game. Screamers with loud sounds are part of the same effect. Players who want to survive must avoid the entities that want them dead and try to save the world, or they lose access to it.
Lostworld requires GeckoLib on Forge, and it runs on client and server, so the server and every player need it. The files target 1.20.1 only, and the latest Forge build is 1.3.9 for 1.20.1. The code is released under All rights reserved, so the mod is not open source.
Key features
Terrifying dimensions
Scary entities and creepy dimensions form the main setting, with the strangest and most terrifying places to escape from.
Glitched liminal levels
Levels such as Level 2 and Level 6 feature endless mazes and unstable spaces to travel through.
Desktop and file scares
Text files with clues and binary codes can be dropped onto the real-life Desktop, and custom Windows pop-ups appear outside the game.
Entity avoidance and survival
Entities that want the player dead must be avoided, and the world must be saved before access to it is lost.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
How it compares
What Is This Dimension is a Forge horror mod for 1.20.1, with client and server environment and All rights reserved licensing. Nocturnia uses the same loader and version and is also under All rights reserved. corrupted_worlds.jar [Horror] is released under the MIT License, while still running on Forge 1.20.1 with both sides required.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Lostworld.jar | Forge | 1.20.1 | Client and server | 2026-06-03 |
| What Is This Dimension | Forge | 1.20.1 | Client and server | 2024-09-29 |
| Nocturnia | Forge | 1.20.1 | Client and server | 2025-08-13 |
| corrupted_worlds.jar [Horror] | Forge | 1.20.1 | Client and server | 2026-08-29 |
Questions
Does Lostworld need GeckoLib?
Does Lostworld have to be installed on the server?
Which game versions does Lostworld support?
In the catalog
Lostworld.jar is one of 7,555 Cursed mods on ModsFinder, and one of 3,426 Cursed mods for Forge. 34,764 mods support Minecraft 1.20.1.
Similar mods
What the author says
Want to immerse yourself in a very suspicious world? You'll see the strangest and most terrifying dimensions, and you'll have to escape from them! Try to avoid entities that want you dead. Try to save your world! Otherwise, you'll lose access to it. This is a psychological meta-horror mod. You don't just survive in…
Official listing
- Modrinth page
- modrinth.com/mod/lostworld.jar
- Owner
- Worldman
- Published
- 2026-05-02
- Updated on Modrinth
- 2026-06-03
- Facts verified
- 2026-10-15