Quark is a fully modular mod with the objective of improving the vanilla gameplay experience. In other words, I would call it "what I would add if I was hired at mojang - the mod". Modules can be turned off and all features can be turned off individually. Some even have more in-depth configs.
For a full breakdown of every feature, please check the Quark Website.
Looking for Quark Oddities? You can download it here.
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