The repack is usually distributed as a single file ( index.html ) that is roughly 20-30 MB. Once downloaded, the game does not stream textures from the internet, making it extremely data-efficient.

This is the elephant in the room. Mojang Studios (Microsoft) has a strict EULA (End User License Agreement). Eaglercraft technically violates the reverse-engineering clause.

A "repack" often aims to provide the smoothest "out-of-the-box" experience by including: