Prism Launcher Mod Loaders
Install or switch Fabric, NeoForge, Forge, Quilt, or LiteLoader on any Minecraft instance in two clicks without manual JAR installers.
Create a Prism instance for Minecraft 1.16.5 on Forge. Use Java 8.
Add Instance → 1.16.5 → install Forge. Assign Java 8 under Settings → Java.
This pairing existed for that version. Older versions are not given NeoForge or Quilt pages.
Installer: /download.

Java 8. Mismatch is a common exit code 1.
Free and open source. Sign in with the Microsoft account that owns Minecraft, then create your first instance.
