In a similar spirit to Freedoom, for Quake fans perhaps you'll want to take a look at LibreQuake, which aims to do a similar thing to allow you to play Quake content with completely open source software.
Wait, so there’s multiple engines?
Someone explain this to me—if I wanted to play free Quake in the simplest way, what exactly would I need to install?
This is not an engine, this is the freedoom equivalent for quake. You will need a quake engine like QuakeSpasmSpiked and then follow the how to play instructions.
Wait, so there’s multiple engines? Someone explain this to me—if I wanted to play free Quake in the simplest way, what exactly would I need to install?
The Flatpak version comes with Quakespasm engine, so you won’t need to worry about the source port.
This is not an engine, this is the freedoom equivalent for quake. You will need a quake engine like QuakeSpasmSpiked and then follow the how to play instructions.