Developer: Quetoo Team
Release Date: May 22, 2026

So this is interesting, I just stumbled on this randomly a few weeks back right after it was released, although it was apparently in the works for twenty years.

Quetoo is an open source project that's a combination of id Tech engines and technologies, incorporating every graphics technique the source port communities are known for, and recreating some of the classic maps of the Quake series without actually using any of its data.

The result is a purely community focused freeware arena shooter that can even be edited with modern tools like Trenchboom.
Definitely one to keep an eye on.