etlegacy VS SRB2

You could try Dirty Bomb or the classic Wolfenstein: Enemy Territory for some class-based objective shooters. Both are free to play.

ET Legacy Wolfenstein Enemy Territory, FOSS client. Maybe moot since an official client re-released on Steam recently.

It doesn't replace any server, it's a new one on Legacy mod - https://www.etlegacy.com/

Look up ETLegacy some nice guys from the old scene have basically remastered it - hd graphics updated sounds etc. All things in one place!

ET: Legacy

Have you tried using ET Legacy? www.etlegacy.com It's basically the same ET client, but updated to current standards.

As you pointed you need source code that can be found here: https://github.com/etlegacy/etlegacy

Off topic, but if it was Wolfenstein ET I will just add that there still is a community for it and a Foss version of it that runs on modern operating systems

https://www.etlegacy.com/

if you're a Sonic fan, you could play free games like Sonic Robo Blast 2 or Sonic and the Fallen Star which are great imo.

Sonic Robo Blast 2: https://www.srb2.org/

Godot does offer Constructive Solid Geometries that can be used for basic prototyping, and can be exported to Blender for additional work. https://docs.godotengine.org/en/stable/tutorials/3d/csg\_tools.html As an alternate engine, you could also consider Sonic Robo Blast 2 https://www.srb2.org/ as a possible engine to work in. Which has been stretched all the way into making a Kart Racer.

Here are a few free games I've played on my tv: C-Dogs SDL, Sonic Robo Blast 2

I would recommend Delta Touch (Doom engine ports), knights of the old republic 1 and 2 (both support mods on android), Sonic Robo Blast 2 (not on play store but at www.srb2.org ), Source Engine android port (portal, half-life 2, also not on play store but can easily be found by googling it)