The air isn't always breathable in caves, at high elevations, or other extreme locations. Equip yourself to mine safely, or face the consequences!
A Fabric/Quilt continuation of Thin Air by Fusz (as the original project was discontinued), which itself was a port of Miner's Lung by Petra.
Additionally, the mod was written with performance in mind, and it should have very minor impacts on TPS. Only players are affected by the need to breathe.
The mod is also highly data-driven and configurable, allowing you to define which blocks emit what air quality, the natural air quality of any dimension at any elevation (and even dimension-specific emitters!); see the guide.
Requires Fabric API (or QSL).
You may include and distribute this mod, unmodified, in modpacks. Do not distribute this mod on its own, and do not download this mod from anywhere other than Modrinth!

The air isn't always breathable in caves, at high elevations, or other extreme locations.