A Minecraft 1.8.9 client built around Hypixel and Prediction anti-cheat, designed so modules just work out of the box.
Arsenic is no longer a Forge mod. It is a jar you run on its own: it finds your running Minecraft 1.8.9 game and attaches at runtime. That works with Vanilla, Forge and Lunar Client, and means nothing ever goes in .minecraft/mods. See the install guide.
The client is built around the Hypixel and Prediction anti-cheats. Anything that gets flagged is removed from the base client. The repository also ships a Grim-safe guide for addon authors, which documents how packet ordering, knockback and simulation checks see a client. No client is undetectable, so always test new modules before relying on them.
The philosophy is to minimise per-module settings so features just work. Combat modules like KillAura, AimAssist and Backtrack use sensible defaults, and v2.0 simplified settings across many modules.
Modules written as plain .java files in ~/Arsenic/addons/ are compiled by an embedded compiler and hot-loaded, with no JDK-side build step. Packs bundle addons for specific games — Bedwars, Pit, HUD, render, QoL, movement and Hypixel utilities. Details on the addons page.
A ClickGUI with theme support, a draggable HUD, a custom main menu and post-processing effects. Module categories are Combat, Movement, Player, Render, Client, Configs and GUI, with a search view across all modules.
Module settings and enabled state are saved in configs. Control the client from chat with dot commands such as .addon new, .addon reload and .addon list. Everything is stored in one Arsenic folder in your home directory, shared across launchers.
A lightweight event bus (@EventLink listeners) and Mixin hooks underpin the client. Addons get the same event bus plus accessor interfaces for private Minecraft state.
The full source is on GitHub with 900+ commits. Build it yourself with JDK 8 — the FAQ has the steps.