Thin Air — NeoForge 1.21.1 Port

A faithful NeoForge port of fuzs's Thin Air. The air is not always breathable deep underground and in other dimensions.

The original mod is archived on Modrinth (last release: Minecraft 1.20.4). This fork brings it forward to Minecraft 1.21.1 on NeoForge while staying close to the upstream design (not a ground-up rewrite) with some features added.

⚠️ Please report bugs for this port only in this repository's issue tracker. Do not contact fuzs about issues specific to this port.

What's Different

• NeoForge-only: Direct port of the 1.20.4 codebase and data, updated for NeoForge 1.21.1 APIs and datapack path changes (recipe/, advancement/, loot_table/, and so on).
• Server-authoritative config: Settings live in thinair-server.toml under each world's serverconfig/ folder, with an optional in-game config screen (Mods menu) via Cloth Config.
• Optional Curios: Respirator uses the Curios head slot and Safety Lantern uses the Curios belt slot when Curios is installed; the mod works without it.
• Optional Create integration: Backtanks provide breathable air in yellow and red air when worn with a Diving Helmet (via Create's own equipment system, with an optional Curios back slot for the backtank itself); like Curios, none of this is required or bundled, the mod loads and works fine with neither installed.
• Work in progress: Full parity testing is ongoing.

Features

• Air quality levels: Green, yellow, red, and blue air affect breathing and what equipment helps, by dimension and height.
• Safety Lantern: Shows nearby air quality by color; can be dyed and scraped with an axe.
• Signal Torch: Right-click to emit particles (configurable).
• Respirator: Protects against choking air (Curios head slot when available).
• Air Bladder / Reinforced Air Bladder: Portable air refill; reinforced variant crafted with netherite and copies durability from the ingredient bladder.
• Bottle of Soulfire: Emergency air restore in the Nether.
• Advancements, recipes, loot injections, drowned air-drain behavior, chunk air-quality sync, and English / Russian / Chinese lang files.

Blocks

• Safety Lantern: shows nearby air quality by color; can be dyed and scraped with an axe
• Signal Torch: right-click to emit particles (configurable)

Items

• Respirator: protects against choking air (Curios head slot when available)
• Air Bladder / Reinforced Air Bladder: portable air refill (reinforced recipe copies bladder durability)
• Bottle of Soulfire: emergency air restore in the Nether

Advancements

• Air Bladder: use an Air Bladder to refill your air supply on the go
• Blue Air: breathe the life force given off by Soul Fire to maintain your air (but not increase it!)
• Disco Lantern: use a piece of Dye to manually change the color of a Safety Lamp (you can scrape the color off with an axe)
• Respirator: protect yourself from choking air with something like a Respirator
• Safety Lantern: use a Safety Lantern to check the air quality around you
• Signal Torch: right-click a torch to make it spew particles, perhaps to signal the exit of a cave
• Soulfire Bottle: restore your lungs with the souls trapped in a Bottle of Soulfire
• Water Breathing: breathe freely where there is no air at all

Known limitations

Work still in progress compared to the original 1.20.4 release:

• Full parity testing (multiplayer, loot, advancements, worldgen-placed air providers) is ongoing

Technical Info

Installation

1. Install NeoForge for Minecraft 1.21.1.
2. Download or build thinair-*.jar from Releases.
3. Drop the mod .jar into your mods/ folder.
4. Optionally install Curios for respirator/lantern slot support, and/or Create for backtank breathable-air support.
5. Launch the game.

After the first launch, change settings from the Mods menu config screen or by editing <world>/serverconfig/thinair-server.toml (air quality, signal torches, drowned choking, and air-provider bubble ranges).

Credits

References

• Changelog
• Original mod on Modrinth
• Original source
• Curios
• Create

License

MIT — same as the original Thin Air project. Asset rights follow the upstream LICENSE-ASSETS terms where applicable.