Avoid enabling "Fast Render" or "Fast Math" unless you know what you are doing, as these can break certain mods or cause graphical artifacts.
Patcher is a performance and bug-fix mod created by for Minecraft version 1.8.9. It’s widely used in the Hypixel community (and other servers) to optimize FPS, reduce lag spikes, and fix several vanilla rendering and gameplay bugs. Patcher Mod Minecraft 1.8.9