The Complex
by cainthetrain
The Complex is a NeoForge mod in the Cursed category that adds liminal, unsettling spaces and content to Minecraft Java Edition for 1.21.4 – 1.21.8.
What it does
The mod builds its atmosphere around places that feel familiar yet wrong, a theme shared with other liminal and backrooms mods. A server running it needs every connecting player to have it too. NeoForge is the only loader, and files cover 1.21.4 and 1.21.8, with 1.2.0 for 1.21.8 as the latest release, published 2026-06-20. The code is licensed under CC0 1.0 Universal, and the mod is not open source.
Key features
Liminal spaces
Eerie, empty areas meant to feel like a place the player has seen before but cannot quite place.
Memory-driven content
Some parts of the mod respond to what the player has already experienced, so the spaces seem to recall past visits.
Prank-friendly design
Certain features are shaped for players who want to surprise friends by sending them into an unfamiliar, unsettling area.
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
Liminal is a NeoForge mod for 1.21.1 – 1.21.8 that is also client and server, with All rights reserved and not open source. TFam's Backrooms Essentials is a NeoForge option only for 1.21.8, with the same environment and license terms. Glowing Blocks is limited to 1.21.1 and is not open source either.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| The Complex | NeoForge | 1.21.4 – 1.21.8 | Client and server | 2026-06-20 |
| Liminal | NeoForge | 1.21.1 – 1.21.8 | Client and server | 2026-10-10 |
| TFam's Backrooms Essentials | NeoForge | 1.21.8 | Client and server | 2026-07-08 |
| Glowing Blocks | NeoForge | 1.21.1 | Client and server | 2025-11-04 |
In the catalog
The Complex is one of 7,555 Cursed mods on ModsFinder, and one of 2,801 Cursed mods for NeoForge. 17,695 mods support Minecraft 1.21.8.
More from cainthetrain
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What the author says
Do you want to prank your friends by putting them into liminal purgatory? This is the mod for you! Actually, more like it... remembers them.
Official listing
- Modrinth page
- modrinth.com/mod/the-complex
- Owner
- cainthetrain
- Published
- 2025-09-20
- Updated on Modrinth
- 2026-06-20
- Facts verified
- 2026-10-15