hey, I was playing with a setting which allowed higher than normal world Y levels and found myself wanting to change the height settings of thin air to allow high level to be breathable but leave low level unbreathable tho realized its not something I could modify or tweak.
Check the dimensions entry in the config, specifically the entry for minecraft:overworld, it demonstrates you you can define specific air quality ranges.
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hey, I was playing with a setting which allowed higher than normal world Y levels and found myself wanting to change the height settings of thin air to allow high level to be breathable but leave low level unbreathable tho realized its not something I could modify or tweak.
Love the idea of the mod btw!